Unveiling Electric-Field-Driven Deformation Dynamics in Metal Nanostructures

Unveiling Electric-Field-Driven Deformation Dynamics in Metal Nanostructures | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Unveiling Electric-Field-Driven Deformation Dynamics in Metal Nanostructures Guodong Meng, Yimeng Li, Linghan Xia, Nan Li, Jianyu Wang, Shilong Tang, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6826850/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 22 Dec, 2025 Read the published version in Nature Communications → Version 1 posted You are reading this latest preprint version Abstract Electric-field-induced damage severely impacts the long-term stability and reliability of nanoelectronic devices with nanogaps, such as field emission nanodiodes, field-effect nanotransistors and especially ultrafast switches recently reported in Nature that demonstrated revolutionary picosecond switching speeds and breakthrough terahertz potential. However, the damage mechanisms behind nanostructured electrode under high electric fields remain unclear. Here, we investigate deformation behaviors of tungsten nanotips, a typical nanostructured electrode, under an external electric field (~ 10 V/nm) using an in situ transmission electron microscopy (TEM), presenting the first direct observation of both surface morphological evolution and dislocation dynamics. We find that electron wind effects and nanoscale effects dramatically reduce the atom evaporation threshold to ~ 10 V/nm, a striking five-fold reduction from the theoretical prediction of ~ 50 V/nm. Furthermore, we identify a novel field-induced deformation mechanism where strong electric fields and emission currents generate substantial, size-dependent structural changes closely governed by crystallographic orientation (Wulff shape) without external heating, occurring primarily through field-assisted evaporation rather than conventionally assumed field-induced surface atom diffusion. These findings enhance the understanding of electric-field-induced damage and are crucial for nanoelectronic devices optimization, reliability, and lifetime evaluation. Physical sciences/Nanoscience and technology/Nanoscale materials/Electronic properties and materials Physical sciences/Engineering/Electrical and electronic engineering Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Significant advances in nanomechanical fabrication techniques have enabled a new generation of nanoelectronic devices, including field emission nanodiodes 1 , 2 , field-effect nanotransistors 3 – 5 , ultrafast switches 6 – 9 , and molecular transistors 10 , 11 , many of which feature a vacuum nanogap as the electron transport channel. This configuration offers advantages such as high electron velocities, fast switching speeds, high thermal stability, and strong radiation resistance. Many of these devices, especially those with asymmetric electrode configurations, operate based on field electron emission 5 , 9 , 12 , 13 , wherein electrons tunnel through the potential barrier at the electrode-vacuum interface under a high electric field. Recent breakthroughs, notably in Nature-reported ultrafast switches, have achieved picosecond-level operation with low power consumption by leveraging field-emission-induced nanoplasma 6 , 7 . However, electric-field-induced damage to nanostructured electrodes during operation remains a major reliability concern, often leading to breakdown, short-circuiting, and ultimately device failure 14 . Despite notable advances in device performance, the microscopic mechanisms underlying such damage remain poorly understood, posing a critical barrier to enhancing the long-term stability and practical application of nanoelectronic devices. Metal structures under high electric fields are generally believed to undergo several phenomena, including field-induced surface atom diffusion 15 – 17 , electromigration driven by electron wind force 18 , 19 , field-assisted evaporation aided by Joule heating 20 or by electron wind force 21 , field evaporation (i.e., surface atoms are directly ionized and then extracted from the surface) 22 – 24 , and field-induced plastic deformations 25 – 27 . At electric field strengths of several GV/m and temperatures around 2000 K, surface atom diffusion becomes dominant, which can reshape field-emitting tips (with radii of a few hundred nanometers) from hemispherical to polyhedral formed with low-index facets 15 , 16 . As electric fields rise to tens of GV/m, field evaporation 22 – 24 and plastic deformations 25 – 27 become more pronounced. High field emission current densities (10 4 to 10 6 A cm − 2 ) can significantly increase electromigration 18 , 19 , where electron wind force and Joule heating may aid surface atom evaporation 20 , 21 . At the nanoscale, however, the deformation behaviors of nanostructures become more complex due to higher surface energy 28 and increased resistivity 29 , making the underlying mechanisms less clear. Up to now, existing in situ electrical studies have primarily focused on electrically assisted dislocation motion, driven by several key mechanisms: electron-dislocation interactions 30 , electron wind forces 31 , and the behavior of charged dislocations 32 . However, the overall response of metal nanostructures or nanoelectrodes remains less explored. Recently, we first in situ observed field-induced surface atom diffusion leading to nano-protrusion formation on a carbon-coated nanoelectrode — a key precursor to electrical breakdown 17 . This raises a crucial question: In an uncoated metal nanostructure under a high electric field, what phenomena emerge, and which deformation mechanisms dominate? This study seeks to clarify these unresolved issues. In this work, we investigate the in situ deformation behaviors of the tungsten nanotips with different apex curvature radii ( R = 3 nm, 5 nm and 9 nm) during field emission at room temperature. For the first time, we report the successful observation of both the gradual top surface shape modification of the nanotips as well as the nucleating and annihilating dislocations within the metal nanostructures during the long exposure to high electric fields and field emission current. Our findings confirm that these phenomena are driven by electron wind effects and field-assisted evaporation. Furthermore, reverse polarity experiments demonstrate that nanoscale effects ( R < 3 nm) alone can also drive morphological transformations, primarily governed by field evaporation. Results Experimental method The electrode deformation behaviors during field emission are tested using an in situ electrical measurement and micromorphology characterization system, which comprises a transmission electron microscopy (JEOL-2100F TEM) and an in situ electrically biased TEM holder (ZepTools Technology) 33 . The electrode structure is tungsten nanotip (W, cathode) - gold plate (Au, anode), and the -oriented tungsten nanotips with different radii ( R = 3 nm, 5 nm and 9 nm) are prepared by a two-step process: the ex situ double‑electrolyte electrochemical etching method 34 and the in situ Joule melting method 35 . In our experiments, we track the deformation behaviors of these nanotips during field emission. The technique details regarding experimental system, experimental process and the preparation of tungsten nanotips are described in the Methods section. The deformation behaviors of tungsten nanotips Figure 1 a-h depicts a sequence of TEM images showcasing the progressive deformation behaviors of a 3 nm tungsten nanotip during field emission. The corresponding field emission current ( I FE ) and the cumulative treatment time ( t ) are annotated in the bottom right corner of each TEM image. Figure 1 i overlays all the extracted surface profiles for comparison. At first sight, the height of nanotip decreases, and the apex morphology shows a spherical to polyhedral (Fig. 1 a-g) and back to close-to-spherical shape (Fig. 1 g-h) transformation. To gain deeper insights into the evolution process, an atomistic model is constructed using molecular dynamics (MD) method 36 . The top view of the model is illustrated in Fig. 1 j, where all relevant facets are highlighted for clarity. Firstly, at an initial I FE = 10 nA and a treatment time of 5 min, we observe the removal of {110} layers and the atoms on the {211} planes as indicated by the white arrow in Fig. 1 b. Notably, for simplicity, we use the curly brackets for the crystallographic facets to emphasize the generality of our observations. As field emission treatment progresses, atoms on the {110} and {211} facets evaporate, and the apex of nanotip gradually evolves into a polyhedral shape following the geometry of these facets, as shown in Fig. 1 c-g. With further field emission treatment (Fig. 1 g-h), the nanotip apex transitions from a polyhedral shape back to the close-to-spherical shape, due to atom evaporation that has flattened the sharp features at the right-side edge and the top of the nanotip, as highlighted by the white arrows in Fig. 1 g. Throughout the experiment, the initial crystal orientation of the nanotip remains largely intact, with minimal dislocations or other defects observed, as confirmed by the Fourier-filtered images in Supplementary Fig. 4. Notably, some blurry boundaries in these TEM images are attributed to the delocalization effect 37 . Fig. 1k shows the applied voltages at which I FE = 2 nA is achieved at a 15 nm gap, demonstrating the change in the field emission capability of different nanotip morphologies. The field emission curves can be found in Supplementary Fig. 5a. It can be seen that with the deformation of the nanotip into a polyhedral shape, its field emission capability increases due to the electric field enhancement at the sharp edges 38 . When the morphology evolves back to a close-to-spherical shape, the field emission capability decreases. Figure 2 a-l show a sequence of the TEM images capturing the progressive deformation behaviors of a 5 nm tungsten nanotip during the field emission treatment ( I FE = 1000 nA). The cumulative treatment time ( t ) is annotated in the bottom right corner of each TEM image. Below each TEM image, the corresponding Fourier-filtered (FFT) images are shown, with the edge dislocations of different polarities marked by magenta and yellow ‘⊥’ symbols, respectively. The corresponding total numbers of dislocations, along with the numbers of dislocations of different polarities for each nanotip morphology, are presented in Fig. 2 o. Figure 2 m overlays all the extracted surface profiles of the nanotips for comparison. It is evident that the deformation of the 5 nm nanotip requires more treatment time compared to that of the 3 nm nanotip. Similar to the evolution process of the 3 nm nanotip, the height of nanotip decreases, and its morphology transitions from a spherical shape (Fig. 2 a) to a polyhedral shape (Fig. 2 h), and then back to a close-to-spherical (Fig. 2 i-j). The top view of the MD model, along with the labeled crystallographic facets, is shown in Fig. 2 n. Firstly, at a I FE = 1000 nA and a treatment time of 30 min, significant atom removal is observed on high-index facets, such as {310}, which mainly bridges the low-index {110} and {100} facets (Fig. 2 n), as highlighted by the black arrows in Fig. 2 b. After approximately 5 min of treatment, noticeable atomic evaporation begins at the edges of the top {110} facet, leaving a shorter {110} facet (Fig. 2 b-c). An additional 5 min of treatment further causes the evaporation of this shorter {110} facet (Fig. 2 b-d). This observation indicates the atom-by-atom evaporation process, which must have taken place also at the top of 3 nm tip, but the 5 min resolution was too long to capture this process (Fig. 1 ). As field emission treatment progresses, the atomic layers from the {110} facets and atoms from the {100} facets gradually evaporate, leading to a transformation of the nanotip into a polyhedral shape composed of the {100} and {110} facets, as observed in Fig. 2 d-h. The corresponding FFT images in Fig. 2 a-h show that during this morphological evolution, the dislocations initially emerge near the surface (Fig. 2 b) and, over time, an increasing number of dislocations appear within the bulk of the nanotip (Fig. 2 c-h), as illustrated in Fig. 2 o. With continued field emission, the apex shape becomes smoother and the polyhedral shape seen in Fig. 2 h evolves into an ellipsoid (or close-to-spherical) (Fig. 2 i-j), and surprisingly, all internal dislocation defects vanish. The annihilation of dislocations is attributed to the vicinity of the open surface, with electron scattering at higher dislocation densities further enhancing the process 31 . Further, the following prolonged field emission treatment (Fig. 2 i-l), shows the nucleation of new dislocations as well as the clear changes in the surface morphology of the tip. Once again, we observe the emergence of a low-index {100} facets (Fig. 2 l) due to obvious atom evaporation, particularly outlined by sharp edges on the left side of the nanotip, along with an increased number of dislocations (Fig. 2 o). Figure 2 p shows the applied voltages at I FE = 2 nA in a 15 nm gap, reflecting the field emission capability of various nanotip morphologies. The field emission curves are provided in Supplementary Fig. 5b. Similarly, as the morphology of the nanotip evolves into a polyhedral shape, field emission capability increases gradually due to the increased electric field at the edges. When the morphology evolves to an ellipsoid shape, the field emission capability again slightly decreases. For the -oriented tungsten nanotip with an apex radius of 9 nm, the TEM images before and after treatment with I FE = 1000 nA for 4 hours are provided in Supplementary Fig. 6. However, it can be seen that the morphology of this tungsten nanotip and the field emission capability remains largely unchanged. Discussion The aforementioned transformation to a polyhedral shape is mainly formed by the low-index {110} and {100} facets, or {110} and {211} facets, indicating that the deformation behaviors align with the Wulff construction of the equilibrium crystal shape (ECS) for body-centred cubic (BCC) crystals, which is governed by the anisotropy of surface free energy 16 . Experiments on tungsten tips with radii of a few hundred nanometers 24 , 25 , conducted under electric field strengths on the order of several GV/m and high temperatures (~ 2000 K), suggest that low energy surfaces tend to grow at the expense of higher energy ones due to field-induced surface atom diffusion. However, our nanoscale experiments reveal the significant atom evaporation during the evolution process. The subsequent transformation back to a close-to-spherical shape is likely driven by a higher electric field strength at the edges and the increased electron scattering on the surfaces of this polyhedral nanotip due to nanoscale effect 13 , 45 , both of which facilitate atomic diffusion and atom evaporation at the edges. In contrast, for emitter tips with radii of a few hundred nanometers, the transformation back to spherical shape requires flashing treatments 16 . To determine the primary driver of deformation in tungsten nanotips during field emission experiments, a systematic analysis and comparison of various physical effects is essential. In our experiments, the electric fields are below 10 V/nm (Supplementary Fig. 8c to Fig. 10c), corresponding to a Maxwell stress σ of less than 0.5 GPa (see Supplementary Note 1 for details). This value is significantly lower than the yield strength of tungsten along the direction, which is 19.2 GPa 39 , so the field-induced plastic deformation 25 – 27 can be excluded. Next, we used the coupled electrodynamics (ED) - Molecular dynamics (MD) - particle-in-cell (PIC) computational tool 36 (as detailed in the Methods section), to obtain the temperature rise caused by field emission current. The obtained temperature distribution (see Supplementary Note 2 for details) shows that the nanotips remain at the steady temperature of approximately 300 K under I FE = 1000 nA, indicating that thermal effects are insignificant globally and at the apex of the nanotip. Notably, temperature rise caused by electron beam (a beam intensity of approximately 4 A/cm 2 ) is minimal (< 1 K) 28 , and during every observation period of 5 to 10 minutes, the morphology of nanotip remains essentially unchanged under electron beam, so the electron beam effect can be ignored. More importantly, nanotips during field emission are subjected to electron wind effects 18 , 19 and electric field effects (field-induced surface atomic diffusion 15 – 17 , field-assisted evaporation 20 , 21 and field evaporation 22 – 24 ). To decouple these effects from field emission, we conducted the reverse polarity experiments on tungsten nanotips (anode) with radii of 2 nm and 5 nm (see Supplementary Note 3 for details), and the deformation results and the corresponding field emission capabilities of both nanotips (tested as cathodes) are shown in Fig. 3 and Fig. 4 , respectively. As can be seen, for the 2 nm tungsten nanotip, the electric field is sufficient to induce a transition in morphology from a spherical shape (Fig. 3 a) to a polyhedral shape (Fig. 3 c-d), formed by the low-index {110}and {100} facets, before reverting back to a close-to-spherical shape (Fig. 3 f). During this deformation, the significant atom evaporation is observed, seen from Fig. 3 g. Similarly, the initial crystal orientation of the nanotip remains largely intact, with minimal dislocations or other defects observed (see Supplementary Fig. 13), and the field emission capability increases slightly as the morphology evolves into a polyhedral shape. However, for the 5 nm tungsten nanotip, the morphology does not transition from a spherical shape to a polyhedral shape during the reverse polarity treatments. Similarly, after approximately 5 min of treatment, we observe the noticeable atomic evaporation at the edges of the top {110} facet, leaving a shorter {110} facet (Fig. 4 b). With the reverse polarity treatment, the atoms evaporate gradually, shortening the nanotip by 0.39 nm, which is less than the 1.25 nm shortening observed in the 5 nm nanotip during field emission treatment (Fig. 2 ). During this process, a few dislocations appear near the surface, while the internal atoms remain still (Fig. 4 ), which is different from the behavior seen in Fig. 2 . Notably, this experiment can be seen as the one that proceeds via similar evaporation process, but slower due to the absence of electron wind effects. During this slow process, we observe a small but significant bulge forming, as indicated by the black arrow in Fig. 4 d, which suggests the presence of field-induced surface atomic diffusion. Additionally, the corresponding field emission capability remains essentially unchanged. As we can see, in the reverse polarity experiments, we observe field evaporation without Joule heating or electron wind effects, particularly the evaporation of edge atoms. This is surprising because the applied electric field in our experiments is significantly lower than the theoretical threshold of ~ 50 V/nm 40–42 , yet it is similar to the high-temperature field evaporation threshold of ~ 10 V/nm 43 . This can be attributed to the enhanced local field and the lower number of neighboring atoms at edge sites 22 , 24 , 44 , especially at the edges of the atomic terraces and on the top plane, which are influenced by the apex radius of the nanotip. Edge atoms have fewer neighboring atoms, resulting in weaker bonding energy compared to atoms in the bulk or central regions of the top plane, making them more susceptible to detachment under an applied electric field 42 , 44 . The higher curvature, reduced atomic coordination, and higher specific surface area of nanotips with small apex radii (e.g., 2 nm in Fig. 3 ) further enhance the local electric field and the surface energy, lowering the energy barrier for evaporation and increasing the likelihood of field evaporation 28 . Notably, surface atom evaporation tends to progress from the edges toward the center 45 . However, as the number of top-plane atoms increases, evaporation slows down, and field-induced surface atom diffusion is observed (Fig. 4 d). Compared to reverse polarity experiments (Fig. 3 and Fig. 4 ), the field emission experiments (Fig. 1 and Fig. 2 ) include electron wind effects. At I FE = 1000 nA, the current densities are approximately 3.54⋅10 6 A cm - 2 , 1.27⋅10 6 A cm -2 and 3.90⋅10 5 A cm - 2 for tungsten nanotips with apex radii of 3 nm, 5 nm and 9 nm, respectively. Despite minimal temperature rise (remaining 300 K, see Supplementary Note 2), estimated electron wind forces reach ~ 3.3⋅10 4 Pa, 1.2⋅10 4 Pa and 3.7⋅10 3 Pa 46 . This indicates that the electron wind force is able to transfer momentum to surface atoms, particularly edge atoms, making them more likely to detach from the surface and undergo field-assisted evaporation. Additionally, due to higher surface stress, dislocations tend to nucleate at the surface rather than within the material 47 . The combined effects of high electric fields and electron wind force enhance the mobility of surface atoms, facilitating dislocation formation and propagation, as evident when comparing Fig. 2 and Fig. 4 . Notably, the above processes are also size-dependent: when the size is relatively large, 9 nm nanotip exhibits minimal morphological changes during field emission due to their lower surface energy and weaker electron wind force. Therefore, during reverse polarity experiments, we observed the pronounced nanoscale effects especially for 2 nm nanotip, field evaporation (though less prominent for the 5 nm nanotip) and field-induced surface atomic diffusion. During the field emission treatment, we observed the significant electron wind effect and its induced field-assisted evaporation. Although field-induced surface atom diffusion may occur due to its lower threshold compared to atom evaporation 42 , it is less noticeable as the rate of field-assisted evaporation surpasses that of surface diffusion 48 . Notably, the nanoscale effects are closely tied to electrode size and become more pronounced as the size decreases. For a 2 nm tungsten nanotip, the electric field alone can induce field evaporation, driving a transition from a spherical shape to a polyhedral structure (Wulff construction) and eventually reverting to a near-spherical form. For a 5 nm nanotip, the electric field is insufficient to independently drive morphological changes to Wulff construction, requiring the assistance of electron wind force to facilitate field-assisted evaporation. However, when the electrode size reaches 9 nm or larger, external temperature may be required to drive morphological evolution, gradually aligning with the thermal-field (TF) conditions observed in the tungsten emitters with radii of a few hundred nanometers 24 , 25 . These findings clarify the microscopic mechanisms behind the shape evolution of metal nanostructures under high electric fields, and reveal that strong electric fields and field emission currents, without external heating, can induce significant morphological deformation of metal nanostructures, with the deformation being size-dependent and closely related to the crystallographic planes. Given tungsten's relative inertness, field-induced damage may be more severe in metals like copper and gold. As such, our research provides crucial insights into field-induced surface damage, enhancing our understanding of the behavior of metal nanostructures under high electric fields. These findings are vital for the design and optimization of reliable nanoelectronic devices. Conclusion In conclusion, the deformation behaviors of typical metal nanostructures, i.e., tungsten nanotips with varying radii ( R = 3 nm, 5 nm and 9 nm) during field emission at room temperature was studied by using an in situ electrical experiment system combined with a transmission electron microscopy (TEM). Our findings provide the first direct observation of external shape deformation along with the internal dislocation evolution of metal nanostructures under high electric fields. We identified a spherical-polyhedral (Wulff construction)-close-to-spherical transformation in nanotips with 3 nm and 5 nm radii, driven primarily by significant electron wind effects and its induced field-assisted evaporation. In contrast, no morphological changes were detected in 9 nm nanotips. Reverse polarity experiments further confirm that nanoscale effects ( R < 3 nm) alone can drive morphological transformations, accompanied by substantial field evaporation. These results provide direct microscopic evidence of the shape deformation of metal nanostructures under high electric fields, which are essential for understanding and mitigating electric-field-induced damage in nanoelectronic devices. Methods In situ electrical measurement and micromorphology characterization system and experimental procedure The in situ electrical measurement and micromorphology characterization system consists of the transmission electron microscopy (JEOL-2100F TEM) and an in situ electrically biased TEM holder (ZepTools Technology). This setup achieves a spatial resolution of 0.1 nm and allows for nanogap adjustment with an accuracy of 0.04 nm. The system can apply a direct current voltage of up to 150 V across nanogaps, with a current measurement resolution of 0.1 nA. Supplementary Fig. 1a-b shows the in situ electrically biased TEM holder and the schematic diagram of the experimental system. All measurements are performed at room temperature and a vacuum level of ~ 10 − 5 Pa. The morphology evolution experiment of pure tungsten nanotips is composed of two periods, the “treatment” period and the “observation” period, as shown in Supplementary Fig. 1c. During the treatment period, which lasts Δ t , the applied voltage is adjusted to maintain a constant field emission current I FE from the tungsten nanotip without any external heating. The morphology of nanotip gradually changes during this treatment period. After the treatment period, the observation period starts, during which the nanotip morphology is recorded by TEM, and the field emission characteristics at 15 nm nanogap are tested. The treatment and observation periods are repeated iteratively to comprehensively monitor the deformation behaviors of tungsten nanotips during field emission. It is important to note that the gap distance is kept at 15 nm during both periods. Fabrication of the pure tungsten nanotips The preparation of the tungsten nanotips involves two steps. The first step is an ex situ double‑electrolyte electrochemical etching method 34 , and the schematic is shown in Supplementary Fig. 2. Specifically, a stepping motor (TSTA-1050, 7-star, Beijing) precisely controls the motion of a 99.97% pure tungsten wire with a diameter of 0.3 mm. The tungsten wire passes through a 5 M NaOH electrolyte lamella (flake, purity 97%, Aladdin) and is immersed perpendicularly in a saturated NaCl solution (AR, Aladdin). A DC power source (B2091A, Keysight, USA) supplies a voltage of 5 V to a stainless steel anode immersed in the saturated NaCl solution and a ring inert nickel-chromium cathode (diameter 10 mm). The tungsten wire is etched only in the NaOH lamella, with the NaCl solution acting as a conducting element between the tungsten wire and the stainless steel anode. Once the tungsten wire breaks, the electric circuit is automatically cut off as the lower fragment of the tungsten wire drops. However, although the curvature radius of the prepared tungsten nanotip by first step is less than 50 nm, there is an unavoidable oxide layer with a few nanometers thick on the tungsten nanoelectrode surface due to the ex situ preparation, which significantly affects the field emission characteristics. The second step is an in situ Joule melting method. Initially, the tungsten nanoelectrodes prepared by the first step and the gold plate (prepared by pressing and cutting) are mounted on the TEM electrical sample holder, as shown in Supplementary Fig. 1a. Next, the interelectrode gap is adjusted in situ to less than 20 nm under TEM. A ramped DC voltage is then applied across the nanogap to induce electrical breakdown, with the tungsten nanotip acting as the cathode and the gold plate as the anode. Following the breakdown, the tungsten nanotips with curvature radius less than 10 nm can be prepared in situ . The TEM images and the selected area electron diffraction (SAED) results of the initial tungsten nanotips with different radii ( R = 3 nm, 5 nm and 9 nm) depicted in Supplementary Fig. 3a-c reveal a surface devoid of contaminants, a round and smooth apex, a neatly arranged lattice with few internal defects and a crystallographic direction parallel to the emitter axis. The coupled electrodynamics (ED) - molecular dynamics (MD) - particle-in-cell (PIC) simulations All ED-MD-PIC simulations are performed using the in-house computational tool named field emission coupled with molecular dynamics (FEcMD) 36 . Here, we established models for the three tungsten nanotips, and accessed the thermal effects induced by a field emission current of 1000 nA in the experiments, with the results detailed in Supplementary Note 2. In the simulations, the distribution of the electric field and the evolution of temperature over time and space is calculated via a finite element mesh. The electron field emission process is described using the Jeffreys-Wentzel-Kramers-Brillouin (JWKB) model, with the GETELEC library fully integrated into the FEcMD software package. Space charge effects on the local electric field distribution are considered due to the use of PIC simulation when solving Poisson equation. Notably, the correction factors between experimental and theoretical field emission characteristics have been considered 49 . The heat conduction process in the nanotip is simulated using the two-temperature model (TTM), where the electron and phonon temperature profiles are calculated separately using heat balance equations on a finite element grid. The electric conductivity and electron thermal conductivity of nanotips are both corrected by the temperature and the nano-size effects. The electron and phonon subsystems are dynamically coupled through electron-phonon energy exchange mechanisms, where the electron-phonon coupling constant is 1.65×10 17 W/(K⋅m 3 ) 50 . A time step of 0.5 fs is applied for calculating the electric field and field emission current density, and a 4 fs time step is used for temperature calculation considering Joule and Nottingham heating effects. Declarations Data Availability The data supporting the findings of this study are available within the main text and supplementary information files. All data are available from the corresponding author upon request. Acknowledgements The work is supported by National Natural Science Foundation of China (51977169), and the China Scholarhip Council program (202406280230). Ethics declarations Competing interests The authors declare no competing interests. References Hernandez, N., Cahay, M., O'Mara, J., Ludwick, J., Walker, D. J. r., Back, T., Hall, H. 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S., Parviainen, S., Muranaka, T., Djurabekova, F. Dislocation nucleation on a near surface void leading to surface protrusion growth under an external electric field. J Appl Phys 114 , 033519 (2013). Kuppart, K., Vigonski, S., Aabloo, A., Wang, Y., Djurabekova, F., Kyritsakis, A., Zadin, V. Mechanism of Spontaneous Surface Modifications on Polycrystalline Cu Due to Electric Fields. Micromachines-Basel 12 , 1178 (2021). Zadin, V., Pohjonen, A., Aabloo, A., Nordlund, K., Djurabekova, F. Electrostatic-elastoplastic simulations of copper surface under high electric fields. Phys Rev Spec Top-Ac 17 , 103501 (2014). Sun, J., He, L. B., Lo, Y. C., Xu, T., Bi, H. C., Sun, L. T., Zhang, Z., Mao, S. X., Li, J. Liquid-like pseudoelasticity of sub-10-nm crystalline silver particles. Nat Mater 13 , 1007-1012 (2014). Han, H. J., Kumar, S., Jin, G. T., Ji, X. Y., Hart, J. L., Hynek, D. J., Sam, Q. P., Hasse, V., Felser, C., Cahill, D. G., Sundararaman, R., Cha, J. J. Topological Metal MoP Nanowire for Interconnect. Adv Mater 35 , 2208965 (2023). Li, X., Zhu, Q., Hong, Y. R., Zheng, H., Wang, J., Wang, J. W., Zhang, Z. Revealing the pulse-induced electroplasticity by decoupling electron wind force. Nat Commun 13 , 6503 (2022). Zhang, X., Li, H. W., Zhan, M., Zheng, Z. B., Gao, J., Shao, G. D. Electron force-induced dislocations annihilation and regeneration of a superalloy through electrical in-situ transmission electron microscopy observations. J Mater Sci Technol 36 , 79-83 (2020). Li, M. Q., Shen, Y. D., Luo, K., An, Q., Gao, P., Xiao, P. H., Zou, Y. Harnessing dislocation motion using an electric field. Nat Mater 22 , 958-963 (2023). Li, Y., Zhan, F., Tang, J., Cheng, Y., Meng, G. Effect of Cathode Radius on the Pre-breakdown Characteristics in Vacuum Nanogaps. 30th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) , 1-4 (2023). Li, B. W., Zhang, Y. P., Wang, J. S., Jia, Z. Z., Shi, C. Q., Ma, Y. Q., Ma, L. Fabricating ultra-sharp tungsten STM tips with high yield: double-electrolyte etching method and machine learning. Sn Appl Sci 2 , 1246 (2020). Meng, G. D., Cheng, Y. H., Wu, K., Chen, L. Electrical Characteristics of Nanometer Gaps in Vacuum under Direct Voltage. IEEE Trans Dielectr Electr Insul 21 , 1950-1956 (2014). Li, N., Gao, X., Feng, X., Wu, K., Cheng, Y., Xiao, B. FEcMD: A multi-physics and multi-scale computational program for electron emission characteristics dynamically coupled with atomic structure in metal nano-emitters. arXiv:231004751 , (2023). Williams, D. B., Carter, C. B., Williams, D. B., Carter, C. B. The transmission electron microscope (Springer, 1996). Yanagisawa, H., Zadin, V., Kunze, K., Hafner, C., Aabloo, A., Kim, D. E., Kling, M. F., Djurabekova, F., Osterwalder, J., Wuensch, W. Laser-induced asymmetric faceting and growth of a nano-protrusion on a tungsten tip. APL Photonics 1 , 091305 (2016). Wang, J. W., Zeng, Z., Weinberger, C. R., Zhang, Z., Zhu, T., Mao, S. X. atomic-scale observation of twinning-dominated deformation in nanoscale body-centred cubic tungsten. Nat Mater 14 , 594-600 (2015). Golubev, O. L. Experimental determination of evaporating electric field strengths for nanodimensional field ion emitters. Tech Phys Lett 40 , 1092-1094 (2014). Tamaki, S., Kuroda, T. Field-Evaporation of Tungsten in Field Ion Microscope. Jpn J Appl Phys 7 , 1202 (1968). Ashton, M., Mishra, A., Neugebauer, J., Freysoldt, C. Description of Bond Breaking in Large Electric Fields. Phys Rev Lett 124 , (2020). Golubev, O. L. High-temperature field evaporation and its connection with surface ionization. Tech Phys 58 , 787-792 (2013). Yao, L., Withrow, T., Restrepo, O. D., Windl, W., Marquis, E. A. Effects of the local structure dependence of evaporation fields on field evaporation behavior. Appl Phys Lett 107 , 241602 (2015). Qi, J. Y. W., Oberdorfer, C., Windl, W., Marquis, E. A. simulation of field evaporation. Phys Rev Mater 6 , 093602 (2022). Zhao, S. T., Zhang, R. P., Chong, Y., Li, X. Q., Abu-Odeh, A., Rothchild, E., Chrzan, D. C., Asta, M., Morris, J. W., Minor, A. M. Defect reconfiguration in a Ti-Al alloy via electroplasticity. Nat Mater 20 , 468-472 (2021). Anderson, P. M., Hirth, J. P., Lothe, J. Theory of dislocations (Cambridge University Press, 2017). Pavlov, V. G. Field desorption microscopy of the ⟨111⟩ trihedral angle of a reconstructed tungsten tip. Tech Phys 51 , 1210-1214 (2006). Meng, G., Li, Y., Xia, L., Li, N., Tang, S., Ge, Y., Wang, J., Xiao, B., Cheng, Y., Ang, L. K. R. Uncovering a universal scaling for the field emission characteristics from metallic nanotips in nanogap. (2024). Daraszewicz, S. L., Giret, Y., Tanimura, H., Duffy, D. M., Shluger, A. L., Tanimura, K. Determination of the electron-phonon coupling constant in tungsten. Appl Phys Lett 105 , 023112 (2014). Additional Declarations There is NO Competing Interest. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6826850","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":473189029,"identity":"bd54efdb-54c4-4bb0-a00c-7f70b51aebb1","order_by":0,"name":"Guodong Meng","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA+klEQVRIiWNgGAWjYFCCBDDJDEQHGCSQRAhr4WFgS2CQSCBBCwMPA48BlENAi7x7duLjgl+H2e0lcr5JWP44zMDPnmPA8HMHbi2GZ95uNp7Zl8bMI5G72UAi4TCDZM8bA8beM3i0zMjdJs3bYwPSsvEBSIvBjRwDZsY2vFq2/+btkQBqyXlwAKTFnpAWeYncbcw8P0C25DBCbJEgoMWA5+1mad4GoF/OPDM2kEhL55E486zgYC8+W9pzN37m+XM4mb09+Zm0hI21HH978sYHP/HZcgBIAJ2RDOIwS4DiBwgO4NYAtKUBRP5hsANRjB/wKR0Fo2AUjIIRCwAkyUzcCicZMQAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0001-6170-9302","institution":"State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an jiaotong university","correspondingAuthor":true,"prefix":"","firstName":"Guodong","middleName":"","lastName":"Meng","suffix":""},{"id":473189030,"identity":"285583b7-b35f-4834-94b3-0bbe1172f3c3","order_by":1,"name":"Yimeng Li","email":"","orcid":"https://orcid.org/0000-0001-9783-9264","institution":"State Key Laboratory of Electrical Insulation and Power Equipment, Xi’an Jiaotong University, Xi’an","correspondingAuthor":false,"prefix":"","firstName":"Yimeng","middleName":"","lastName":"Li","suffix":""},{"id":473189031,"identity":"8a18346c-a1e3-4fb6-b6e7-a50f6669d448","order_by":2,"name":"Linghan Xia","email":"","orcid":"","institution":"State Key Laboratory of Electrical Insulation and Power Equipment, Xi’an Jiaotong University, Xi’an","correspondingAuthor":false,"prefix":"","firstName":"Linghan","middleName":"","lastName":"Xia","suffix":""},{"id":473189032,"identity":"aea3d932-3703-4e5f-b5cc-36490ff4a64c","order_by":3,"name":"Nan Li","email":"","orcid":"","institution":"State Key Laboratory of Electrical Insulation and Power Equipment, Xi’an Jiaotong University, Xi’an","correspondingAuthor":false,"prefix":"","firstName":"Nan","middleName":"","lastName":"Li","suffix":""},{"id":473189033,"identity":"7b50e699-d988-4f29-920b-6df8f8c55eb0","order_by":4,"name":"Jianyu Wang","email":"","orcid":"","institution":"State Key Laboratory of Electrical Insulation and Power Equipment, Xi’an Jiaotong University, Xi’an","correspondingAuthor":false,"prefix":"","firstName":"Jianyu","middleName":"","lastName":"Wang","suffix":""},{"id":473189034,"identity":"e5e2b898-8bb9-48ad-a343-1f2fdac15f83","order_by":5,"name":"Shilong Tang","email":"","orcid":"","institution":"State Key Laboratory of Electrical Insulation and Power Equipment, Xi’an Jiaotong University, Xi’an","correspondingAuthor":false,"prefix":"","firstName":"Shilong","middleName":"","lastName":"Tang","suffix":""},{"id":473189035,"identity":"782123f6-d4a6-4d72-8c06-bb39202b7efa","order_by":6,"name":"Yunsong Ge","email":"","orcid":"","institution":"State Key Laboratory of Electrical Insulation and Power Equipment, Xi’an Jiaotong University, Xi’an","correspondingAuthor":false,"prefix":"","firstName":"Yunsong","middleName":"","lastName":"Ge","suffix":""},{"id":473189036,"identity":"6b1e345c-ce80-4621-a907-66563dee0644","order_by":7,"name":"Bing Xiao","email":"","orcid":"","institution":"Xi'an Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Bing","middleName":"","lastName":"Xiao","suffix":""},{"id":473189037,"identity":"be34feb9-b5f8-4382-a675-78361e2c1e09","order_by":8,"name":"Yonghong Cheng","email":"","orcid":"","institution":"Center of Nanomaterials for Renewable Energy (CNRE), State Key Laboratory of Electrical Insulation and Power Equipment, School of Electrical Engineering, Xi’an Jiaotong University, Xi’an","correspondingAuthor":false,"prefix":"","firstName":"Yonghong","middleName":"","lastName":"Cheng","suffix":""},{"id":473189038,"identity":"337b3ebb-dc4f-414f-9cb4-d81af2625795","order_by":9,"name":"Zhi-Wei Shan","email":"","orcid":"https://orcid.org/0000-0002-4533-0869","institution":"Xi'an Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Zhi-Wei","middleName":"","lastName":"Shan","suffix":""},{"id":473189039,"identity":"c1c74aff-65f9-44eb-aeae-03e841064559","order_by":10,"name":"Flyura Djurabekova","email":"","orcid":"https://orcid.org/0000-0002-5828-200X","institution":"University of Helsinki","correspondingAuthor":false,"prefix":"","firstName":"Flyura","middleName":"","lastName":"Djurabekova","suffix":""}],"badges":[],"createdAt":"2025-06-05 08:20:46","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6826850/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6826850/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41467-025-67972-2","type":"published","date":"2025-12-22T05:00:00+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":84945836,"identity":"7c544ff8-3594-42ad-8b2e-c4b6a0c96833","added_by":"auto","created_at":"2025-06-19 06:09:01","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":346643,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea-h \u003c/strong\u003eTEM images showing the progressive deformation behaviors of a \u0026lt;110\u0026gt;-oriented tungsten nanotip with an apex radius of 3 nm during field emission. The corresponding field emission current (\u003cem\u003eI\u003c/em\u003e\u003csub\u003eFE\u003c/sub\u003e) and the cumulative treatment time (\u003cem\u003et\u003c/em\u003e) are indicated in the lower right corner of each image. \u003cstrong\u003ei\u003c/strong\u003e The surface profiles of tungsten nanotips. \u003cstrong\u003ej\u003c/strong\u003e The top view of the MD model of a \u0026lt;110\u0026gt;-oriented tungsten nanotip with an apex radius of 3 nm. \u003cstrong\u003ek\u003c/strong\u003e The applied voltages required to achieve a field emission current of 2 nA (\u003cem\u003ed\u003c/em\u003e = 15 nm) is plotted in relation to the morphology changes of this tungsten nanotip.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-6826850/v1/6a5c593cba9da97517ff4e79.png"},{"id":84946132,"identity":"4dc3855b-47e6-4b38-adff-597aa318feb9","added_by":"auto","created_at":"2025-06-19 06:17:00","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":618885,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea-l \u003c/strong\u003eTEM images above showing the progressive deformation behaviors of a \u0026lt;110\u0026gt;-oriented tungsten nanotip with an apex radius of 5 nm after each field emission treatment (\u003cem\u003eI\u003c/em\u003e\u003csub\u003eFE\u003c/sub\u003e = 1000 nA) period. Below each TEM image, the corresponding Fourier-filtered images depict the evolution of dislocations, with the edge dislocations of different polarities marked by magenta and yellow ‘^’ symbols, respectively. The cumulative treatment time (\u003cem\u003et\u003c/em\u003e) are indicated in the lower right corner of each TEM image. \u003cstrong\u003em\u003c/strong\u003e The collection of all morphological profiles. \u003cstrong\u003en\u003c/strong\u003e The top view of the MD model of a \u0026lt;110\u0026gt;-oriented tungsten nanotip with an apex radius of 5 nm. \u003cstrong\u003eo\u003c/strong\u003e The total numbers of dislocations, along with the numbers of dislocations of different polarites for each nanotip morphology. \u003cstrong\u003ep\u003c/strong\u003e The applied voltages required to achieve a field emission current of 2 nA (\u003cem\u003ed\u003c/em\u003e = 15 nm) is plotted in relation to the morphology changes of this tungsten nanotip.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-6826850/v1/73cf518b5cdbd686624b117c.png"},{"id":84946133,"identity":"12a17ec3-4534-4b8a-ba52-fc72473400d6","added_by":"auto","created_at":"2025-06-19 06:17:01","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":283288,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea-f \u003c/strong\u003eTEM images showing the progressive deformation behaviors of a \u0026lt;110\u0026gt;-oriented tungsten nanotip with an apex radius of 2 nm during the reverse polarity treatment. The cumulative treatment time (\u003cem\u003et\u003c/em\u003e) are indicated in the lower right corner of each image. \u003cstrong\u003eg\u003c/strong\u003e The collection of all morphological profiles. \u003cstrong\u003eh \u003c/strong\u003eThe top view of the MD model of a \u0026lt;110\u0026gt;-oriented tungsten nanotip with an apex radius of 2 nm.\u003cstrong\u003e i\u003c/strong\u003e The applied voltages required to achieve a field emission current of 2 nA (\u003cem\u003ed\u003c/em\u003e = 15 nm) is plotted in relation to the morphology changes of this tungsten nanotip.\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-6826850/v1/4ddb51476bf7444e1976141b.png"},{"id":84945834,"identity":"7395dff5-ee54-4c14-a68c-261adafbd16d","added_by":"auto","created_at":"2025-06-19 06:09:01","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":457052,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea-j \u003c/strong\u003eTEM images above showing the progressive deformation behaviors of a \u0026lt;110\u0026gt;-oriented tungsten nanotip with an apex radius of 5 nm during reverse polarity treatment. The cumulative treatment time (\u003cem\u003et\u003c/em\u003e) are indicated in the lower right corner of each image. Below each TEM image, the corresponding Fourier-filtered images depict the evolution of dislocations, with the edge dislocations of different polarities marked by magenta and yellow ‘^’ symbols, respectively. \u003cstrong\u003ek\u003c/strong\u003e The collection of all morphological profiles. \u003cstrong\u003el\u003c/strong\u003eThe top view of the MD model of a \u0026lt;110\u0026gt;-oriented tungsten nanotip with an apex radius of 5 nm. \u003cstrong\u003em\u003c/strong\u003e The total numbers of dislocations, along with the numbers of dislocations of different polarites for each nanotip morphology. \u003cstrong\u003en \u003c/strong\u003eThe applied voltages required to achieve a field emission current of 2 nA (\u003cem\u003ed\u003c/em\u003e = 15 nm) is plotted in relation to the morphology changes of this tungsten nanotip.\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-6826850/v1/c9a48b70b75d3b72c01160ee.png"},{"id":99212632,"identity":"9db26f8a-d7e1-4da6-b523-ed2387d0295b","added_by":"auto","created_at":"2025-12-30 08:25:31","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2313662,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6826850/v1/d0c05008-4f0c-45e6-9ec8-52e1da2b5689.pdf"},{"id":84946635,"identity":"5783553b-dd52-4a67-b5eb-21aae9d8e7cf","added_by":"auto","created_at":"2025-06-19 06:25:01","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":22845066,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryInformation.docx","url":"https://assets-eu.researchsquare.com/files/rs-6826850/v1/f172ec5116ddef259286322d.docx"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Unveiling Electric-Field-Driven Deformation Dynamics in Metal Nanostructures","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSignificant advances in nanomechanical fabrication techniques have enabled a new generation of nanoelectronic devices, including field emission nanodiodes\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e, field-effect nanotransistors \u003csup\u003e\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e, ultrafast switches\u003csup\u003e\u003cspan additionalcitationids=\"CR7 CR8\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e, and molecular transistors\u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e, many of which feature a vacuum nanogap as the electron transport channel. This configuration offers advantages such as high electron velocities, fast switching speeds, high thermal stability, and strong radiation resistance. Many of these devices, especially those with asymmetric electrode configurations, operate based on field electron emission \u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e, wherein electrons tunnel through the potential barrier at the electrode-vacuum interface under a high electric field. Recent breakthroughs, notably in Nature-reported ultrafast switches, have achieved picosecond-level operation with low power consumption by leveraging field-emission-induced nanoplasma \u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e. However, electric-field-induced damage to nanostructured electrodes during operation remains a major reliability concern, often leading to breakdown, short-circuiting, and ultimately device failure\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e. Despite notable advances in device performance, the microscopic mechanisms underlying such damage remain poorly understood, posing a critical barrier to enhancing the long-term stability and practical application of nanoelectronic devices.\u003c/p\u003e \u003cp\u003eMetal structures under high electric fields are generally believed to undergo several phenomena, including field-induced surface atom diffusion\u003csup\u003e\u003cspan additionalcitationids=\"CR16\" citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e, electromigration driven by electron wind force\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e, field-assisted evaporation aided by Joule heating\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e or by electron wind force\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e, field evaporation (i.e., surface atoms are directly ionized and then extracted from the surface)\u003csup\u003e\u003cspan additionalcitationids=\"CR23\" citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e, and field-induced plastic deformations\u003csup\u003e\u003cspan additionalcitationids=\"CR26\" citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u003c/sup\u003e. At electric field strengths of several GV/m and temperatures around 2000 K, surface atom diffusion becomes dominant, which can reshape field-emitting tips (with radii of a few hundred nanometers) from hemispherical to polyhedral formed with low-index facets\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e. As electric fields rise to tens of GV/m, field evaporation\u003csup\u003e\u003cspan additionalcitationids=\"CR23\" citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e and plastic deformations\u003csup\u003e\u003cspan additionalcitationids=\"CR26\" citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u003c/sup\u003e become more pronounced. High field emission current densities (10\u003csup\u003e4\u003c/sup\u003e to 10\u003csup\u003e6\u003c/sup\u003e A cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e) can significantly increase electromigration\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e, where electron wind force and Joule heating may aid surface atom evaporation\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e. At the nanoscale, however, the deformation behaviors of nanostructures become more complex due to higher surface energy\u003csup\u003e\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u003c/sup\u003e and increased resistivity\u003csup\u003e\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e\u003c/sup\u003e, making the underlying mechanisms less clear.\u003c/p\u003e \u003cp\u003eUp to now, existing \u003cem\u003ein situ\u003c/em\u003e electrical studies have primarily focused on electrically assisted dislocation motion, driven by several key mechanisms: electron-dislocation interactions\u003csup\u003e\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u003c/sup\u003e, electron wind forces\u003csup\u003e\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e\u003c/sup\u003e, and the behavior of charged dislocations\u003csup\u003e\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e. However, the overall response of metal nanostructures or nanoelectrodes remains less explored. Recently, we first \u003cem\u003ein situ\u003c/em\u003e observed field-induced surface atom diffusion leading to nano-protrusion formation on a carbon-coated nanoelectrode \u0026mdash; a key precursor to electrical breakdown\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e. This raises a crucial question: In an uncoated metal nanostructure under a high electric field, what phenomena emerge, and which deformation mechanisms dominate? This study seeks to clarify these unresolved issues.\u003c/p\u003e \u003cp\u003eIn this work, we investigate the \u003cem\u003ein situ\u003c/em\u003e deformation behaviors of the tungsten nanotips with different apex curvature radii (\u003cem\u003eR\u003c/em\u003e\u0026thinsp;=\u0026thinsp;3 nm, 5 nm and 9 nm) during field emission at room temperature. For the first time, we report the successful observation of both the gradual top surface shape modification of the nanotips as well as the nucleating and annihilating dislocations within the metal nanostructures during the long exposure to high electric fields and field emission current. Our findings confirm that these phenomena are driven by electron wind effects and field-assisted evaporation. Furthermore, reverse polarity experiments demonstrate that nanoscale effects (\u003cem\u003eR\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;3 nm) alone can also drive morphological transformations, primarily governed by field evaporation.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eExperimental method\u003c/p\u003e\n\u003cp\u003eThe electrode deformation behaviors during field emission are tested using an \u003cem\u003ein situ\u003c/em\u003e electrical measurement and micromorphology characterization system, which comprises a transmission electron microscopy (JEOL-2100F TEM) and an \u003cem\u003ein situ\u003c/em\u003e electrically biased TEM holder (ZepTools Technology)\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e33\u003c/span\u003e\u003c/sup\u003e. The electrode structure is tungsten nanotip (W, cathode) - gold plate (Au, anode), and the \u0026lt;\u0026thinsp;110\u0026gt;-oriented tungsten nanotips with different radii (\u003cem\u003eR\u003c/em\u003e\u0026thinsp;=\u0026thinsp;3 nm, 5 nm and 9 nm) are prepared by a two-step process: the \u003cem\u003eex situ\u003c/em\u003e double‑electrolyte electrochemical etching method\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e34\u003c/span\u003e\u003c/sup\u003e and the \u003cem\u003ein situ\u003c/em\u003e Joule melting method\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e35\u003c/span\u003e\u003c/sup\u003e. In our experiments, we track the deformation behaviors of these nanotips during field emission. The technique details regarding experimental system, experimental process and the preparation of tungsten nanotips are described in the Methods section.\u003c/p\u003e\n\u003cp\u003eThe deformation behaviors of tungsten nanotips\u003c/p\u003e\n\u003cp\u003eFigure \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003ea-h depicts a sequence of TEM images showcasing the progressive deformation behaviors of a 3 nm tungsten nanotip during field emission. The corresponding field emission current (\u003cem\u003eI\u003c/em\u003e\u003csub\u003eFE\u003c/sub\u003e) and the cumulative treatment time (\u003cem\u003et\u003c/em\u003e) are annotated in the bottom right corner of each TEM image. Figure \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003ei overlays all the extracted surface profiles for comparison. At first sight, the height of nanotip decreases, and the apex morphology shows a spherical to polyhedral (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003ea-g) and back to close-to-spherical shape (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eg-h) transformation. To gain deeper insights into the evolution process, an atomistic model is constructed using molecular dynamics (MD) method\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e36\u003c/span\u003e\u003c/sup\u003e. The top view of the model is illustrated in Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003ej, where all relevant facets are highlighted for clarity. Firstly, at an initial \u003cem\u003eI\u003c/em\u003e\u003csub\u003eFE\u003c/sub\u003e = 10 nA and a treatment time of 5 min, we observe the removal of {110} layers and the atoms on the {211} planes as indicated by the white arrow in Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eb. Notably, for simplicity, we use the curly brackets for the crystallographic facets to emphasize the generality of our observations. As field emission treatment progresses, atoms on the {110} and {211} facets evaporate, and the apex of nanotip gradually evolves into a polyhedral shape following the geometry of these facets, as shown in Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003ec-g. With further field emission treatment (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eg-h), the nanotip apex transitions from a polyhedral shape back to the close-to-spherical shape, due to atom evaporation that has flattened the sharp features at the right-side edge and the top of the nanotip, as highlighted by the white arrows in Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eg. Throughout the experiment, the initial crystal orientation of the nanotip remains largely intact, with minimal dislocations or other defects observed, as confirmed by the Fourier-filtered images in Supplementary Fig. 4. Notably, some blurry boundaries in these TEM images are attributed to the delocalization effect\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e37\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eFig. 1k shows the applied voltages at which \u003cem\u003eI\u003c/em\u003e\u003csub\u003eFE\u003c/sub\u003e = 2 nA is achieved at a 15 nm gap, demonstrating the change in the field emission capability of different nanotip morphologies. The field emission curves can be found in Supplementary Fig. 5a. It can be seen that with the deformation of the nanotip into a polyhedral shape, its field emission capability increases due to the electric field enhancement at the sharp edges\u003csup\u003e38\u003c/sup\u003e. When the morphology evolves back to a close-to-spherical shape, the field emission capability decreases.\u003c/p\u003e\n\u003cp\u003eFigure \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003ea-l show a sequence of the TEM images capturing the progressive deformation behaviors of a 5 nm tungsten nanotip during the field emission treatment (\u003cem\u003eI\u003c/em\u003e\u003csub\u003eFE\u003c/sub\u003e = 1000 nA). The cumulative treatment time (\u003cem\u003et\u003c/em\u003e) is annotated in the bottom right corner of each TEM image. Below each TEM image, the corresponding Fourier-filtered (FFT) images are shown, with the edge dislocations of different polarities marked by magenta and yellow \u0026lsquo;\u0026perp;\u0026rsquo; symbols, respectively. The corresponding total numbers of dislocations, along with the numbers of dislocations of different polarities for each nanotip morphology, are presented in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eo. Figure \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003em overlays all the extracted surface profiles of the nanotips for comparison. It is evident that the deformation of the 5 nm nanotip requires more treatment time compared to that of the 3 nm nanotip. Similar to the evolution process of the 3 nm nanotip, the height of nanotip decreases, and its morphology transitions from a spherical shape (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003ea) to a polyhedral shape (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eh), and then back to a close-to-spherical (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003ei-j). The top view of the MD model, along with the labeled crystallographic facets, is shown in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003en. Firstly, at a \u003cem\u003eI\u003c/em\u003e\u003csub\u003eFE\u003c/sub\u003e = 1000 nA and a treatment time of 30 min, significant atom removal is observed on high-index facets, such as {310}, which mainly bridges the low-index {110} and {100} facets (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003en), as highlighted by the black arrows in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eb. After approximately 5 min of treatment, noticeable atomic evaporation begins at the edges of the top {110} facet, leaving a shorter {110} facet (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eb-c). An additional 5 min of treatment further causes the evaporation of this shorter {110} facet (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eb-d). This observation indicates the atom-by-atom evaporation process, which must have taken place also at the top of 3 nm tip, but the 5 min resolution was too long to capture this process (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). As field emission treatment progresses, the atomic layers from the {110} facets and atoms from the {100} facets gradually evaporate, leading to a transformation of the nanotip into a polyhedral shape composed of the {100} and {110} facets, as observed in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003ed-h. The corresponding FFT images in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003ea-h show that during this morphological evolution, the dislocations initially emerge near the surface (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eb) and, over time, an increasing number of dislocations appear within the bulk of the nanotip (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003ec-h), as illustrated in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eo. With continued field emission, the apex shape becomes smoother and the polyhedral shape seen in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eh evolves into an ellipsoid (or close-to-spherical) (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003ei-j), and surprisingly, all internal dislocation defects vanish. The annihilation of dislocations is attributed to the vicinity of the open surface, with electron scattering at higher dislocation densities further enhancing the process\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e31\u003c/span\u003e\u003c/sup\u003e. Further, the following prolonged field emission treatment (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003ei-l), shows the nucleation of new dislocations as well as the clear changes in the surface morphology of the tip. Once again, we observe the emergence of a low-index {100} facets (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003el) due to obvious atom evaporation, particularly outlined by sharp edges on the left side of the nanotip, along with an increased number of dislocations (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eo).\u003c/p\u003e\n\u003cp\u003eFigure \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003ep shows the applied voltages at \u003cem\u003eI\u003c/em\u003e\u003csub\u003eFE\u003c/sub\u003e = 2 nA in a 15 nm gap, reflecting the field emission capability of various nanotip morphologies. The field emission curves are provided in Supplementary Fig. 5b. Similarly, as the morphology of the nanotip evolves into a polyhedral shape, field emission capability increases gradually due to the increased electric field at the edges. When the morphology evolves to an ellipsoid shape, the field emission capability again slightly decreases.\u003c/p\u003e\n\u003cp\u003eFor the \u0026lt;\u0026thinsp;110\u0026gt;-oriented tungsten nanotip with an apex radius of 9 nm, the TEM images before and after treatment with \u003cem\u003eI\u003c/em\u003e\u003csub\u003eFE\u003c/sub\u003e = 1000 nA for 4 hours are provided in Supplementary Fig. 6. However, it can be seen that the morphology of this tungsten nanotip and the field emission capability remains largely unchanged.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe aforementioned transformation to a polyhedral shape is mainly formed by the low-index {110} and {100} facets, or {110} and {211} facets, indicating that the deformation behaviors align with the Wulff construction of the equilibrium crystal shape (ECS) for body-centred cubic (BCC) crystals, which is governed by the anisotropy of surface free energy\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e. Experiments on tungsten tips with radii of a few hundred nanometers\u003csup\u003e\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u003c/sup\u003e, conducted under electric field strengths on the order of several GV/m and high temperatures (~\u0026thinsp;2000 K), suggest that low energy surfaces tend to grow at the expense of higher energy ones due to field-induced surface atom diffusion. However, our nanoscale experiments reveal the significant atom evaporation during the evolution process. The subsequent transformation back to a close-to-spherical shape is likely driven by a higher electric field strength at the edges and the increased electron scattering on the surfaces of this polyhedral nanotip due to nanoscale effect\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e\u003c/sup\u003e, both of which facilitate atomic diffusion and atom evaporation at the edges. In contrast, for emitter tips with radii of a few hundred nanometers, the transformation back to spherical shape requires flashing treatments\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eTo determine the primary driver of deformation in tungsten nanotips during field emission experiments, a systematic analysis and comparison of various physical effects is essential. In our experiments, the electric fields are below 10 V/nm (Supplementary Fig.\u0026nbsp;8c to Fig.\u0026nbsp;10c), corresponding to a Maxwell stress σ of less than 0.5 GPa (see Supplementary Note 1 for details). This value is significantly lower than the yield strength of tungsten along the \u0026lt;\u0026thinsp;110\u0026thinsp;\u0026gt;\u0026thinsp;direction, which is 19.2 GPa\u003csup\u003e\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e\u003c/sup\u003e, so the field-induced plastic deformation\u003csup\u003e\u003cspan additionalcitationids=\"CR26\" citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u003c/sup\u003e can be excluded. Next, we used the coupled electrodynamics (ED) - Molecular dynamics (MD) - particle-in-cell (PIC) computational tool\u003csup\u003e\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e\u003c/sup\u003e (as detailed in the Methods section), to obtain the temperature rise caused by field emission current. The obtained temperature distribution (see Supplementary Note 2 for details) shows that the nanotips remain at the steady temperature of approximately 300 K under \u003cem\u003eI\u003c/em\u003e\u003csub\u003eFE\u003c/sub\u003e = 1000 nA, indicating that thermal effects are insignificant globally and at the apex of the nanotip. Notably, temperature rise caused by electron beam (a beam intensity of approximately 4 A/cm\u003csup\u003e2\u003c/sup\u003e) is minimal (\u0026lt;\u0026thinsp;1 K)\u003csup\u003e\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u003c/sup\u003e, and during every observation period of 5 to 10 minutes, the morphology of nanotip remains essentially unchanged under electron beam, so the electron beam effect can be ignored.\u003c/p\u003e \u003cp\u003eMore importantly, nanotips during field emission are subjected to electron wind effects\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e and electric field effects (field-induced surface atomic diffusion\u003csup\u003e\u003cspan additionalcitationids=\"CR16\" citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e, field-assisted evaporation\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e and field evaporation\u003csup\u003e\u003cspan additionalcitationids=\"CR23\" citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e). To decouple these effects from field emission, we conducted the reverse polarity experiments on tungsten nanotips (anode) with radii of 2 nm and 5 nm (see Supplementary Note 3 for details), and the deformation results and the corresponding field emission capabilities of both nanotips (tested as cathodes) are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, respectively. As can be seen, for the 2 nm tungsten nanotip, the electric field is sufficient to induce a transition in morphology from a spherical shape (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ea) to a polyhedral shape (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ec-d), formed by the low-index {110}and {100} facets, before reverting back to a close-to-spherical shape (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ef). During this deformation, the significant atom evaporation is observed, seen from Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eg. Similarly, the initial crystal orientation of the nanotip remains largely intact, with minimal dislocations or other defects observed (see Supplementary Fig.\u0026nbsp;13), and the field emission capability increases slightly as the morphology evolves into a polyhedral shape. However, for the 5 nm tungsten nanotip, the morphology does not transition from a spherical shape to a polyhedral shape during the reverse polarity treatments. Similarly, after approximately 5 min of treatment, we observe the noticeable atomic evaporation at the edges of the top {110} facet, leaving a shorter {110} facet (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb). With the reverse polarity treatment, the atoms evaporate gradually, shortening the nanotip by 0.39 nm, which is less than the 1.25 nm shortening observed in the 5 nm nanotip during field emission treatment (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). During this process, a few dislocations appear near the surface, while the internal atoms remain still (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e), which is different from the behavior seen in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. Notably, this experiment can be seen as the one that proceeds via similar evaporation process, but slower due to the absence of electron wind effects. During this slow process, we observe a small but significant bulge forming, as indicated by the black arrow in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ed, which suggests the presence of field-induced surface atomic diffusion. Additionally, the corresponding field emission capability remains essentially unchanged.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAs we can see, in the reverse polarity experiments, we observe field evaporation without Joule heating or electron wind effects, particularly the evaporation of edge atoms. This is surprising because the applied electric field in our experiments is significantly lower than the theoretical threshold of ~\u0026thinsp;50 V/nm\u003csup\u003e40\u0026ndash;42\u003c/sup\u003e, yet it is similar to the high-temperature field evaporation threshold of ~\u0026thinsp;10 V/nm\u003csup\u003e43\u003c/sup\u003e. This can be attributed to the enhanced local field and the lower number of neighboring atoms at edge sites\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e\u003c/sup\u003e, especially at the edges of the atomic terraces and on the top plane, which are influenced by the apex radius of the nanotip. Edge atoms have fewer neighboring atoms, resulting in weaker bonding energy compared to atoms in the bulk or central regions of the top plane, making them more susceptible to detachment under an applied electric field\u003csup\u003e\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e, \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e\u003c/sup\u003e. The higher curvature, reduced atomic coordination, and higher specific surface area of nanotips with small apex radii (e.g., 2 nm in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) further enhance the local electric field and the surface energy, lowering the energy barrier for evaporation and increasing the likelihood of field evaporation\u003csup\u003e\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u003c/sup\u003e. Notably, surface atom evaporation tends to progress from the edges toward the center\u003csup\u003e\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e\u003c/sup\u003e. However, as the number of top-plane atoms increases, evaporation slows down, and field-induced surface atom diffusion is observed (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ed).\u003c/p\u003e \u003cp\u003eCompared to reverse polarity experiments (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e), the field emission experiments (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e) include electron wind effects. At \u003cem\u003eI\u003c/em\u003e\u003csub\u003eFE\u003c/sub\u003e = 1000 nA, the current densities are approximately 3.54\u0026sdot;10\u003csup\u003e6\u003c/sup\u003e A cm\u003csup\u003e-\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e, 1.27\u0026sdot;10\u003csup\u003e6\u003c/sup\u003e A cm\u003csup\u003e-2\u003c/sup\u003e and 3.90\u0026sdot;10\u003csup\u003e5\u003c/sup\u003e A cm\u003csup\u003e-\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e for tungsten nanotips with apex radii of 3 nm, 5 nm and 9 nm, respectively. Despite minimal temperature rise (remaining 300 K, see Supplementary Note 2), estimated electron wind forces reach\u0026thinsp;~\u0026thinsp;3.3\u0026sdot;10\u003csup\u003e4\u003c/sup\u003e Pa, 1.2\u0026sdot;10\u003csup\u003e4\u003c/sup\u003e Pa and 3.7\u0026sdot;10\u003csup\u003e3\u003c/sup\u003e Pa\u003csup\u003e\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e\u003c/sup\u003e. This indicates that the electron wind force is able to transfer momentum to surface atoms, particularly edge atoms, making them more likely to detach from the surface and undergo field-assisted evaporation. Additionally, due to higher surface stress, dislocations tend to nucleate at the surface rather than within the material\u003csup\u003e\u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e\u003c/sup\u003e. The combined effects of high electric fields and electron wind force enhance the mobility of surface atoms, facilitating dislocation formation and propagation, as evident when comparing Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e. Notably, the above processes are also size-dependent: when the size is relatively large, 9 nm nanotip exhibits minimal morphological changes during field emission due to their lower surface energy and weaker electron wind force.\u003c/p\u003e \u003cp\u003eTherefore, during reverse polarity experiments, we observed the pronounced nanoscale effects especially for 2 nm nanotip, field evaporation (though less prominent for the 5 nm nanotip) and field-induced surface atomic diffusion. During the field emission treatment, we observed the significant electron wind effect and its induced field-assisted evaporation. Although field-induced surface atom diffusion may occur due to its lower threshold compared to atom evaporation\u003csup\u003e\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e\u003c/sup\u003e, it is less noticeable as the rate of field-assisted evaporation surpasses that of surface diffusion\u003csup\u003e\u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e\u003c/sup\u003e. Notably, the nanoscale effects are closely tied to electrode size and become more pronounced as the size decreases. For a 2 nm tungsten nanotip, the electric field alone can induce field evaporation, driving a transition from a spherical shape to a polyhedral structure (Wulff construction) and eventually reverting to a near-spherical form. For a 5 nm nanotip, the electric field is insufficient to independently drive morphological changes to Wulff construction, requiring the assistance of electron wind force to facilitate field-assisted evaporation. However, when the electrode size reaches 9 nm or larger, external temperature may be required to drive morphological evolution, gradually aligning with the thermal-field (TF) conditions observed in the tungsten emitters with radii of a few hundred nanometers\u003csup\u003e\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u003c/sup\u003e. These findings clarify the microscopic mechanisms behind the shape evolution of metal nanostructures under high electric fields, and reveal that strong electric fields and field emission currents, without external heating, can induce significant morphological deformation of metal nanostructures, with the deformation being size-dependent and closely related to the crystallographic planes. Given tungsten's relative inertness, field-induced damage may be more severe in metals like copper and gold. As such, our research provides crucial insights into field-induced surface damage, enhancing our understanding of the behavior of metal nanostructures under high electric fields. These findings are vital for the design and optimization of reliable nanoelectronic devices.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn conclusion, the deformation behaviors of typical metal nanostructures, i.e., tungsten nanotips with varying radii (\u003cem\u003eR\u003c/em\u003e\u0026thinsp;=\u0026thinsp;3 nm, 5 nm and 9 nm) during field emission at room temperature was studied by using an \u003cem\u003ein situ\u003c/em\u003e electrical experiment system combined with a transmission electron microscopy (TEM). Our findings provide the first direct observation of external shape deformation along with the internal dislocation evolution of metal nanostructures under high electric fields. We identified a spherical-polyhedral (Wulff construction)-close-to-spherical transformation in nanotips with 3 nm and 5 nm radii, driven primarily by significant electron wind effects and its induced field-assisted evaporation. In contrast, no morphological changes were detected in 9 nm nanotips. Reverse polarity experiments further confirm that nanoscale effects (\u003cem\u003eR\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;3 nm) alone can drive morphological transformations, accompanied by substantial field evaporation. These results provide direct microscopic evidence of the shape deformation of metal nanostructures under high electric fields, which are essential for understanding and mitigating electric-field-induced damage in nanoelectronic devices.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e \u003cem\u003eIn situ\u003c/em\u003e electrical measurement and micromorphology characterization system and experimental procedure\u003c/p\u003e \u003cp\u003eThe \u003cem\u003ein situ\u003c/em\u003e electrical measurement and micromorphology characterization system consists of the transmission electron microscopy (JEOL-2100F TEM) and an \u003cem\u003ein situ\u003c/em\u003e electrically biased TEM holder (ZepTools Technology). This setup achieves a spatial resolution of 0.1 nm and allows for nanogap adjustment with an accuracy of 0.04 nm. The system can apply a direct current voltage of up to 150 V across nanogaps, with a current measurement resolution of 0.1 nA. Supplementary Fig.\u0026nbsp;1a-b shows the \u003cem\u003ein situ\u003c/em\u003e electrically biased TEM holder and the schematic diagram of the experimental system. All measurements are performed at room temperature and a vacuum level of ~\u0026thinsp;10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e Pa.\u003c/p\u003e \u003cp\u003eThe morphology evolution experiment of pure tungsten nanotips is composed of two periods, the \u0026ldquo;treatment\u0026rdquo; period and the \u0026ldquo;observation\u0026rdquo; period, as shown in Supplementary Fig.\u0026nbsp;1c. During the treatment period, which lasts Δ\u003cem\u003et\u003c/em\u003e, the applied voltage is adjusted to maintain a constant field emission current \u003cem\u003eI\u003c/em\u003e\u003csub\u003eFE\u003c/sub\u003e from the tungsten nanotip without any external heating. The morphology of nanotip gradually changes during this treatment period. After the treatment period, the observation period starts, during which the nanotip morphology is recorded by TEM, and the field emission characteristics at 15 nm nanogap are tested. The treatment and observation periods are repeated iteratively to comprehensively monitor the deformation behaviors of tungsten nanotips during field emission. It is important to note that the gap distance is kept at 15 nm during both periods.\u003c/p\u003e \u003cp\u003eFabrication of the pure tungsten nanotips\u003c/p\u003e \u003cp\u003eThe preparation of the tungsten nanotips involves two steps. The first step is an \u003cem\u003eex situ\u003c/em\u003e double‑electrolyte electrochemical etching method\u003csup\u003e\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e\u003c/sup\u003e, and the schematic is shown in Supplementary Fig.\u0026nbsp;2. Specifically, a stepping motor (TSTA-1050, 7-star, Beijing) precisely controls the motion of a 99.97% pure tungsten wire with a diameter of 0.3 mm. The tungsten wire passes through a 5 M NaOH electrolyte lamella (flake, purity 97%, Aladdin) and is immersed perpendicularly in a saturated NaCl solution (AR, Aladdin). A DC power source (B2091A, Keysight, USA) supplies a voltage of 5 V to a stainless steel anode immersed in the saturated NaCl solution and a ring inert nickel-chromium cathode (diameter 10 mm). The tungsten wire is etched only in the NaOH lamella, with the NaCl solution acting as a conducting element between the tungsten wire and the stainless steel anode. Once the tungsten wire breaks, the electric circuit is automatically cut off as the lower fragment of the tungsten wire drops. However, although the curvature radius of the prepared tungsten nanotip by first step is less than 50 nm, there is an unavoidable oxide layer with a few nanometers thick on the tungsten nanoelectrode surface due to the \u003cem\u003eex situ\u003c/em\u003e preparation, which significantly affects the field emission characteristics.\u003c/p\u003e \u003cp\u003eThe second step is an \u003cem\u003ein situ\u003c/em\u003e Joule melting method. Initially, the tungsten nanoelectrodes prepared by the first step and the gold plate (prepared by pressing and cutting) are mounted on the TEM electrical sample holder, as shown in Supplementary Fig.\u0026nbsp;1a. Next, the interelectrode gap is adjusted \u003cem\u003ein situ\u003c/em\u003e to less than 20 nm under TEM. A ramped DC voltage is then applied across the nanogap to induce electrical breakdown, with the tungsten nanotip acting as the cathode and the gold plate as the anode. Following the breakdown, the tungsten nanotips with curvature radius less than 10 nm can be prepared \u003cem\u003ein situ\u003c/em\u003e. The TEM images and the selected area electron diffraction (SAED) results of the initial tungsten nanotips with different radii (\u003cem\u003eR\u003c/em\u003e\u0026thinsp;=\u0026thinsp;3 nm, 5 nm and 9 nm) depicted in Supplementary Fig.\u0026nbsp;3a-c reveal a surface devoid of contaminants, a round and smooth apex, a neatly arranged lattice with few internal defects and a\u0026thinsp;\u0026lt;\u0026thinsp;110\u0026thinsp;\u0026gt;\u0026thinsp;crystallographic direction parallel to the emitter axis.\u003c/p\u003e \u003cp\u003eThe coupled electrodynamics (ED) - molecular dynamics (MD) - particle-in-cell (PIC) simulations\u003c/p\u003e \u003cp\u003eAll ED-MD-PIC simulations are performed using the in-house computational tool named field emission coupled with molecular dynamics (FEcMD)\u003csup\u003e\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e\u003c/sup\u003e. Here, we established models for the three tungsten nanotips, and accessed the thermal effects induced by a field emission current of 1000 nA in the experiments, with the results detailed in Supplementary Note 2.\u003c/p\u003e \u003cp\u003eIn the simulations, the distribution of the electric field and the evolution of temperature over time and space is calculated via a finite element mesh. The electron field emission process is described using the Jeffreys-Wentzel-Kramers-Brillouin (JWKB) model, with the GETELEC library fully integrated into the FEcMD software package. Space charge effects on the local electric field distribution are considered due to the use of PIC simulation when solving Poisson equation. Notably, the correction factors between experimental and theoretical field emission characteristics have been considered\u003csup\u003e\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e49\u003c/span\u003e\u003c/sup\u003e. The heat conduction process in the nanotip is simulated using the two-temperature model (TTM), where the electron and phonon temperature profiles are calculated separately using heat balance equations on a finite element grid. The electric conductivity and electron thermal conductivity of nanotips are both corrected by the temperature and the nano-size effects. The electron and phonon subsystems are dynamically coupled through electron-phonon energy exchange mechanisms, where the electron-phonon coupling constant is 1.65\u0026times;10\u003csup\u003e17\u003c/sup\u003e W/(K\u0026sdot;m\u003csup\u003e3\u003c/sup\u003e)\u003csup\u003e50\u003c/sup\u003e. A time step of 0.5 fs is applied for calculating the electric field and field emission current density, and a 4 fs time step is used for temperature calculation considering Joule and Nottingham heating effects.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eData Availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data supporting the findings of this study are available within the main text and supplementary information files. All data are available from the corresponding author upon request.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe work is supported by National Natural Science Foundation of China (51977169), and the China Scholarhip Council program (202406280230).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics declarations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCompeting\u0026nbsp;interests\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eHernandez, N., Cahay, M., O\u0026apos;Mara, J., Ludwick, J., Walker, D. J. r., Back, T., Hall, H. Field emission characteristics of AlGaN/GaN nanoscale lateral vacuum diodes. \u003cem\u003eJ Appl Phys\u003c/em\u003e \u003cstrong\u003e135\u003c/strong\u003e, 204305 (2024).\u003c/li\u003e\n\u003cli\u003eXu, J., Wang, Q. L., Tao, Z., Zhai, Y. S., Chen, G. D. A., Qi, Z. Y., Zhang, X. B. 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Determination of the electron-phonon coupling constant in tungsten. \u003cem\u003eAppl Phys Lett\u003c/em\u003e \u003cstrong\u003e105\u003c/strong\u003e, 023112 (2014).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"nature-portfolio","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"","title":"Nature Portfolio","twitterHandle":"","acdcEnabled":false,"dfaEnabled":false,"editorialSystem":"ejp","reportingPortfolio":"","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6826850/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6826850/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eElectric-field-induced damage severely impacts the long-term stability and reliability of nanoelectronic devices with nanogaps, such as field emission nanodiodes, field-effect nanotransistors and especially ultrafast switches recently reported in Nature that demonstrated revolutionary picosecond switching speeds and breakthrough terahertz potential. However, the damage mechanisms behind nanostructured electrode under high electric fields remain unclear. Here, we investigate deformation behaviors of tungsten nanotips, a typical nanostructured electrode, under an external electric field (~\u0026thinsp;10 V/nm) using an \u003cem\u003ein situ\u003c/em\u003e transmission electron microscopy (TEM), presenting the first direct observation of both surface morphological evolution and dislocation dynamics. We find that electron wind effects and nanoscale effects dramatically reduce the atom evaporation threshold to ~\u0026thinsp;10 V/nm, a striking five-fold reduction from the theoretical prediction of ~\u0026thinsp;50 V/nm. Furthermore, we identify a novel field-induced deformation mechanism where strong electric fields and emission currents generate substantial, size-dependent structural changes closely governed by crystallographic orientation (Wulff shape) without external heating, occurring primarily through field-assisted evaporation rather than conventionally assumed field-induced surface atom diffusion. These findings enhance the understanding of electric-field-induced damage and are crucial for nanoelectronic devices optimization, reliability, and lifetime evaluation.\u003c/p\u003e","manuscriptTitle":"Unveiling Electric-Field-Driven Deformation Dynamics in Metal Nanostructures","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-19 06:08:55","doi":"10.21203/rs.3.rs-6826850/v1","editorialEvents":[],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"nature-communications","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"NCOMMS","sideBox":"Learn more about [Nature Communications](http://www.nature.com/ncomms/)","snPcode":"","submissionUrl":"https://mts-ncomms.nature.com/","title":"Nature Communications","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature Communications","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"dc9af9e7-5f12-4bbc-a5e0-df92f2465be2","owner":[],"postedDate":"June 19th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":50253368,"name":"Physical sciences/Nanoscience and technology/Nanoscale materials/Electronic properties and materials"},{"id":50253369,"name":"Physical sciences/Engineering/Electrical and electronic engineering"}],"tags":[],"updatedAt":"2025-12-30T08:25:26+00:00","versionOfRecord":{"articleIdentity":"rs-6826850","link":"https://doi.org/10.1038/s41467-025-67972-2","journal":{"identity":"nature-communications","isVorOnly":false,"title":"Nature Communications"},"publishedOn":"2025-12-22 05:00:00","publishedOnDateReadable":"December 22nd, 2025"},"versionCreatedAt":"2025-06-19 06:08:55","video":"","vorDoi":"10.1038/s41467-025-67972-2","vorDoiUrl":"https://doi.org/10.1038/s41467-025-67972-2","workflowStages":[]},"version":"v1","identity":"rs-6826850","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6826850","identity":"rs-6826850","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}