Wafer-scale Low-Noise 266 nm Deep Ultraviolet All-Solid-State Laser

Wafer-scale Low-Noise 266 nm Deep Ultraviolet All-Solid-State Laser | 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 Research Article Wafer-scale Low-Noise 266 nm Deep Ultraviolet All-Solid-State Laser Xikun Xu, Saiyu Luo, Li Li This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7565380/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This paper addresses the demand for wafer-level low-noise deep ultraviolet lasers in precision machining and spectral detection fields by designing and constructing an all-solid-state 532 nm green light and 266 nm deep ultraviolet laser system. The system employs a BBO crystal as the frequency-doubling crystal, achieving efficient conversion of 532 nm green light to 266 nm deep ultraviolet light via external-cavity frequency-doubling technology. Experimental results demonstrate that at a 20 kHz repetition rate, the system outputs laser pulses with a width of 11 ns. The 532 nm laser achieves a peak power of 14 W, while the 266 nm deep ultraviolet laser delivers watt-level output (peak power 1 W). Both lasers exhibit excellent beam quality (M²x = 1.25, M²y = 1.15) and low noise characteristics, meeting the demands of high-stability applications. All-solid-state laser Out-cavity frequency doubling 266 nm deep ultraviolet Pulse Beam quality Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 1 Introduction The deep ultraviolet (DUV) band typically refers to the spectral region with wavelengths between 200 and 300 nm, holding significant importance in high-end applications such as semiconductor lithography, biomolecular detection, precision material processing, and laser-induced breakdown spectroscopy (LIBS)(Li 2015). Specifically, the 266 nm laser—obtained as the output of a near-infrared laser through a quadruple-frequency conversion process—offers advantages such as high monochromaticity, short wavelength, and high photon energy(Pascu 2013; Fang 2017). This makes it an ideal light source for achieving high-resolution, high-sensitivity optical detection and micro/nano fabrication(Orii 2022). Currently, 266 nm lasers are typically generated through a two-step second-harmonic generation process (1064 nm → 532 nm → 266 nm) using a 1064 nm laser source(Chaitanya 2015). In this process, the selected laser gain medium plays a decisive role in the overall system performance. Nd:YVO₄ crystals have gained widespread application in high-repetition-rate short-pulse lasers due to their high absorption coefficient, large gain coefficient, and inherent linearly polarized output characteristics(Kuryak 2020 ). Compared to Nd:YAG, Nd:YVO₄ emits linearly polarized light, significantly enhancing phase-matching efficiency in nonlinear frequency-doubling processes. This makes it particularly suitable for generating second and fourth harmonics at wavelengths such as 532 nm and 266 nm(Cai 2015). However, achieving a 266 nm laser with wafer-level power, stable output, and low noise remains challenging. Key obstacles include selecting nonlinear crystals and designing phase-matching configurations, controlling beam quality along the frequency-doubling path, managing thermal effects within the system, and ensuring overall structural stability. While traditional intracavity frequency-doubling systems offer efficiency advantages, they suffer from structural complexity, difficult tuning, and poor thermal stability(Rao 2018). To address the aforementioned issues, this paper designs and constructs a cavity-external frequency-doubling structure for a wafer-scale, low-noise 266 nm deep ultraviolet pulsed laser system. Operating at high repetition rates, the system pumps 1064 nm laser output, which undergoes second-harmonic generation through an LBO crystal to 532 nm. This output then undergoes fourth-harmonic generation through an out-of-cavity BBO crystal to 266 nm. The final output achieves 11 ns pulse width, 20 kHz repetition rate, and 1 W peak power at the 266 nm wavelength, delivering terawatt-level low-noise deep ultraviolet laser output with excellent beam quality (M²x = 1.25, M²y = 1.15), with power stability exhibiting an RMS noise level of only 0.5%. This makes it suitable for applications demanding exceptional stability and low noise, such as high-precision detection and micro-machining. 2 Laser System Design and Assembly This study constructed an all-solid-state deep ultraviolet laser system. The overall system design adopted a modular approach, sequentially assembling components from the pump source, gain medium, modulator, frequency-doubling crystal, to the output stage. The laser delivers pulses with a width of 11 ns, a repetition rate of 20 kHz, and a peak power of 1 W. Through external-cavity frequency doubling, it ultimately produces a deep ultraviolet laser output at 266 nm. In this system, we selected an LBO crystal as the second-harmonic generation crystal, with anti-reflective coatings for both surfaces at 1064 nm and 532 nm. Its cut angle \(\theta ={90^o}\) , \(\varphi ={0^o}\) , dimensions are 5×5×10 mm. A BBO crystal is selected as the quadruple-frequency crystal. One side of the BBO crystal is coated with 1064 nm and 532 nm anti-reflective coatings, while the other side is coated with 1064 nm, 532 nm, and 266 nm anti-reflective coatings. Its cutting angle \(\theta ={47.7^o}\) , \(\varphi ={0^o}\) , Dimensions are 4×4×7 mm. Both frequency doubling stages are Class I phase-matched. The system optical path diagram is shown in Fig. 1. The Nd:YVO 4 crystal possesses a high absorption cross-section and high gain characteristics, making it a commonly used gain medium for high-efficiency lasers. It exhibits excellent absorption efficiency for pump light near the 808 nm wavelength, enabling efficient conversion to 1064 nm laser output. This system employs a dual-end pumping configuration, introducing 808 nm pump light into both ends of the gain crystal. The pump light enters the Nd:YVO₄ crystal and outputs 1064 nm laser light. An AOM modulator is positioned within the optical cavity. Driven by radiofrequency, it achieves modulation at a 20 kHz repetition rate. By adjusting the AOM, the laser output time window is controlled to produce a narrow 10 ns pulse width. Finally, the modulated 1064 nm laser is output. The 1064 nm laser enters the LBO frequency-doubling crystal, outputting 532 nm green light. A plane mirror coated with a 532 nm high-reflectivity film redirects the optical path. Subsequently, it passes through the BBO crystal to output 266 nm ultraviolet light. A filter removes the green light from the output, isolating the ultraviolet light. This ultimately yields a 266 nm deep ultraviolet pulsed laser with a pulse width of 11 ns, a repetition rate of 20 kHz, a peak power of approximately 1 W, and a power stability with RMS noise of 0.5%. 3 Experimental Results and Analysis The spectrum of this laser at 266 nm was measured using a PG2000 spectrometer with a pump power of 10 W, as shown in Fig. 2. The center wavelength of the output laser is 266.02 nm, consistent with the theoretical design value. The full width at half maximum (FWHM) is approximately 0.12 nm, indicating that the second-harmonic output exhibits high monochromaticity and excellent coherence. Extended testing revealed wavelength drift not exceeding 0.02 nm, demonstrating the stability and reliability of the external-cavity frequency-doubling structure and temperature control system. Using a spectrum analyzer to measure the laser reveals a repetition rate of 20 kHz, with a pulse width of 11 ns, as shown in Fig. 3: By adjusting the input current of the LD pump source, the 808 nm pump light power can be modified. Figure 4(a) shows the current-dependent curves for the 532 nm green light and 266 nm ultraviolet light powers, both of which increase with rising current. Figure 4(b) depicts the 266 nm power as a function of 532 nm power, exhibiting a largely linear relationship. The figures reveal that when the current reaches approximately 33 A, the ultraviolet light reaches its threshold power of 17 mW. At around 50 A, both the green and ultraviolet light powers peak at 14 W and 1 W, respectively, yielding a light-to-light conversion efficiency of approximately 7.14%. The power meter recorded the 1-hour power stability measurement curve of the laser, with an RMS instability of 0.5%, as shown in Fig. 5: The beam quality of the ultraviolet light measured using a beam quality analyzer is, and the ultraviolet light spot pattern was recorded using a CCD camera, as shown in Fig. 6: 4 Conclusion This paper describes the design and successful implementation of a dual-end-pumped, all-solid-state, watt-class, low-noise deep ultraviolet laser system. It operates at an output wavelength of 266 nm, with a pulse width of 11 ns, a repetition rate of 20 kHz, and a peak power of 1 W. The power stability exhibits an RMS noise level of only 0.5%. The system employs two-stage nonlinear frequency doubling: LBO conversion from 1064 nm to 532 nm, followed by BBO conversion from 532 nm to 266 nm. The green-to-UV conversion efficiency reaches 7.14%, enabling stable and efficient deep ultraviolet pulsed laser output. In the experiment, an AOM acousto-optic modulator was employed for pulse modulation. The dual-end pumping structure effectively enhanced pumping efficiency and improved thermal management performance. The entire system demonstrated excellent compactness, output stability, and beam quality. Through systematic component selection and optical path optimization, this paper demonstrates the feasibility and practicality of a deep ultraviolet laser system based on an all-solid-state laser and out-of-cavity frequency doubling technology. This watt-level low-noise laser holds promising applications in material microfabrication, deep ultraviolet lithography, and biological detection. Future work may focus on enhancing beam quality, optimizing thermal management structures, and improving module integration to achieve industrial applications with higher power and repetition rates. Declarations Author Contribution X. wrote the main manuscript text and L. prepared figures 2-3. All authors reviewed the manuscript. References Cai, B.Y., Mao, X., Hou, H., et al.: Double-pulse laser ablation sampling: Enhancement of analyte emission by a second laser pulse at 213 nm. Spectrochim Acta B Spectrosc. 110 , 51–55 (2015) Chaitanya Kumar, S., Canals Casals, J., Sanchez Bautista, E., et al.: Yb-fiber-laser-based, 1.8 W average power, picosecond ultraviolet source at 266 nm. Opt. Lett. 40 (10), 2397–2400 (2015) Fang, Z., Hou, Z., Yang, F., et al.: High-efficiency UV generation at 266 nm in a new nonlinear optical crystal NaSr₃Be₃B₃O₉F₄. Opt. Express. 25 (22), 26500–26507 (2017) Kuryak, A.N., Tikhomirov, B.A.: Role of water vapour in the absorption of nanosecond 266-nm laser pulses by atmospheric air. Quantum Electron. 50 (9), 876 (2020) Li, X., Wang, Z., Fu, Y., et al.: Wavelength dependence in the analysis of carbon content in coal by nanosecond 266 nm and 1064 nm laser induced breakdown spectroscopy. Plasma Sci. Technol. 17 (8), 621 (2015) Orii, Y., Kohno, K., Tanaka, H., et al.: Stable 10,000-hour operation of 20-W deep ultraviolet laser generation at 266 nm. Opt. Express. 30 (7), 11797–11808 (2022) Pascu, M.L., Danko, B., Martins, A., et al.: Exposure of chlorpromazine to 266 nm laser beam generates new species with antibacterial properties: contributions to development of a new process for drug discovery. PLoS One 8 (2), e55767 (2013) Rao, A.S., Chaitanya, N.A., Samanta, G.K.: High-power, high repetition-rate, ultrafast fibre laser based source of DUV radiation at 266 nm. OSA Contin. 2 (1), 99–106 (2018) Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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1","display":"","copyAsset":false,"role":"figure","size":48391,"visible":true,"origin":"","legend":"\u003cp\u003eSystem Structure Diagram\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7565380/v1/33e045a3b865b8a17a164213.png"},{"id":94120869,"identity":"b83ff2ea-60d7-47ba-ad2c-d718dd63a4cc","added_by":"auto","created_at":"2025-10-22 15:06:31","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":79467,"visible":true,"origin":"","legend":"\u003cp\u003eSpectral diagram at 266 nm with pump power of 10 W\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7565380/v1/199583d8fe2077fcd2202d16.png"},{"id":94120441,"identity":"ae0ede81-9674-432d-901d-6f2a5e9da291","added_by":"auto","created_at":"2025-10-22 14:58:31","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":857087,"visible":true,"origin":"","legend":"\u003cp\u003eRepetition frequency 20 kHz and pulse width 10 ns\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7565380/v1/56f7aaa6e58bc3757c881234.png"},{"id":94120872,"identity":"91042492-370c-4796-8f85-edca4ed799b1","added_by":"auto","created_at":"2025-10-22 15:06:31","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":82486,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea\u003c/strong\u003e Variation of 532 nm and 266 nm power with current, \u003cstrong\u003eb\u003c/strong\u003e Variation of 266 nm power with 532 nm 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detection, precision material processing, and laser-induced breakdown spectroscopy (LIBS)(Li 2015). Specifically, the 266 nm laser\u0026mdash;obtained as the output of a near-infrared laser through a quadruple-frequency conversion process\u0026mdash;offers advantages such as high monochromaticity, short wavelength, and high photon energy(Pascu 2013; Fang 2017). This makes it an ideal light source for achieving high-resolution, high-sensitivity optical detection and micro/nano fabrication(Orii 2022).\u003c/p\u003e\u003cp\u003eCurrently, 266 nm lasers are typically generated through a two-step second-harmonic generation process (1064 nm \u0026rarr; 532 nm \u0026rarr; 266 nm) using a 1064 nm laser source(Chaitanya 2015). In this process, the selected laser gain medium plays a decisive role in the overall system performance. Nd:YVO₄ crystals have gained widespread application in high-repetition-rate short-pulse lasers due to their high absorption coefficient, large gain coefficient, and inherent linearly polarized output characteristics(Kuryak \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Compared to Nd:YAG, Nd:YVO₄ emits linearly polarized light, significantly enhancing phase-matching efficiency in nonlinear frequency-doubling processes. This makes it particularly suitable for generating second and fourth harmonics at wavelengths such as 532 nm and 266 nm(Cai 2015).\u003c/p\u003e\u003cp\u003eHowever, achieving a 266 nm laser with wafer-level power, stable output, and low noise remains challenging. Key obstacles include selecting nonlinear crystals and designing phase-matching configurations, controlling beam quality along the frequency-doubling path, managing thermal effects within the system, and ensuring overall structural stability. While traditional intracavity frequency-doubling systems offer efficiency advantages, they suffer from structural complexity, difficult tuning, and poor thermal stability(Rao 2018).\u003c/p\u003e\u003cp\u003eTo address the aforementioned issues, this paper designs and constructs a cavity-external frequency-doubling structure for a wafer-scale, low-noise 266 nm deep ultraviolet pulsed laser system. Operating at high repetition rates, the system pumps 1064 nm laser output, which undergoes second-harmonic generation through an LBO crystal to 532 nm. This output then undergoes fourth-harmonic generation through an out-of-cavity BBO crystal to 266 nm. The final output achieves 11 ns pulse width, 20 kHz repetition rate, and 1 W peak power at the 266 nm wavelength, delivering terawatt-level low-noise deep ultraviolet laser output with excellent beam quality (M\u0026sup2;x\u0026thinsp;=\u0026thinsp;1.25, M\u0026sup2;y\u0026thinsp;=\u0026thinsp;1.15), with power stability exhibiting an RMS noise level of only 0.5%. This makes it suitable for applications demanding exceptional stability and low noise, such as high-precision detection and micro-machining.\u003c/p\u003e"},{"header":"2 Laser System Design and Assembly","content":"\u003cp\u003eThis study constructed an all-solid-state deep ultraviolet laser system. The overall system design adopted a modular approach, sequentially assembling components from the pump source, gain medium, modulator, frequency-doubling crystal, to the output stage. The laser delivers pulses with a width of 11 ns, a repetition rate of 20 kHz, and a peak power of 1 W. Through external-cavity frequency doubling, it ultimately produces a deep ultraviolet laser output at 266 nm.\u003c/p\u003e\u003cp\u003eIn this system, we selected an LBO crystal as the second-harmonic generation crystal, with anti-reflective coatings for both surfaces at 1064 nm and 532 nm. Its cut angle \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\theta ={90^o}\\)\u003c/span\u003e\u003c/span\u003e, \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\varphi ={0^o}\\)\u003c/span\u003e\u003c/span\u003e, dimensions are 5\u0026times;5\u0026times;10 mm. A BBO crystal is selected as the quadruple-frequency crystal. One side of the BBO crystal is coated with 1064 nm and 532 nm anti-reflective coatings, while the other side is coated with 1064 nm, 532 nm, and 266 nm anti-reflective coatings. Its cutting angle \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\theta ={47.7^o}\\)\u003c/span\u003e\u003c/span\u003e, \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\varphi ={0^o}\\)\u003c/span\u003e\u003c/span\u003e, Dimensions are 4\u0026times;4\u0026times;7 mm. Both frequency doubling stages are Class I phase-matched.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe system optical path diagram is shown in Fig.\u0026nbsp;1. The Nd:YVO\u003csub\u003e4\u003c/sub\u003e crystal possesses a high absorption cross-section and high gain characteristics, making it a commonly used gain medium for high-efficiency lasers. It exhibits excellent absorption efficiency for pump light near the 808 nm wavelength, enabling efficient conversion to 1064 nm laser output. This system employs a dual-end pumping configuration, introducing 808 nm pump light into both ends of the gain crystal. The pump light enters the Nd:YVO₄ crystal and outputs 1064 nm laser light. An AOM modulator is positioned within the optical cavity. Driven by radiofrequency, it achieves modulation at a 20 kHz repetition rate. By adjusting the AOM, the laser output time window is controlled to produce a narrow 10 ns pulse width. Finally, the modulated 1064 nm laser is output. The 1064 nm laser enters the LBO frequency-doubling crystal, outputting 532 nm green light. A plane mirror coated with a 532 nm high-reflectivity film redirects the optical path. Subsequently, it passes through the BBO crystal to output 266 nm ultraviolet light. A filter removes the green light from the output, isolating the ultraviolet light. This ultimately yields a 266 nm deep ultraviolet pulsed laser with a pulse width of 11 ns, a repetition rate of 20 kHz, a peak power of approximately 1 W, and a power stability with RMS noise of 0.5%.\u003c/p\u003e"},{"header":"3 Experimental Results and Analysis","content":"\u003cp\u003eThe spectrum of this laser at 266 nm was measured using a PG2000 spectrometer with a pump power of 10 W, as shown in Fig.\u0026nbsp;2. The center wavelength of the output laser is 266.02 nm, consistent with the theoretical design value. The full width at half maximum (FWHM) is approximately 0.12 nm, indicating that the second-harmonic output exhibits high monochromaticity and excellent coherence. Extended testing revealed wavelength drift not exceeding 0.02 nm, demonstrating the stability and reliability of the external-cavity frequency-doubling structure and temperature control system.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eUsing a spectrum analyzer to measure the laser reveals a repetition rate of 20 kHz, with a pulse width of 11 ns, as shown in Fig.\u0026nbsp;3:\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eBy adjusting the input current of the LD pump source, the 808 nm pump light power can be modified. Figure\u0026nbsp;4(a) shows the current-dependent curves for the 532 nm green light and 266 nm ultraviolet light powers, both of which increase with rising current. Figure\u0026nbsp;4(b) depicts the 266 nm power as a function of 532 nm power, exhibiting a largely linear relationship. The figures reveal that when the current reaches approximately 33 A, the ultraviolet light reaches its threshold power of 17 mW. At around 50 A, both the green and ultraviolet light powers peak at 14 W and 1 W, respectively, yielding a light-to-light conversion efficiency of approximately 7.14%.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe power meter recorded the 1-hour power stability measurement curve of the laser, with an RMS instability of 0.5%, as shown in Fig.\u0026nbsp;5:\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe beam quality of the ultraviolet light measured using a beam quality analyzer is, and the ultraviolet light spot pattern was recorded using a CCD camera, as shown in Fig.\u0026nbsp;6:\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"4 Conclusion","content":"\u003cp\u003eThis paper describes the design and successful implementation of a dual-end-pumped, all-solid-state, watt-class, low-noise deep ultraviolet laser system. It operates at an output wavelength of 266 nm, with a pulse width of 11 ns, a repetition rate of 20 kHz, and a peak power of 1 W. The power stability exhibits an RMS noise level of only 0.5%. The system employs two-stage nonlinear frequency doubling: LBO conversion from 1064 nm to 532 nm, followed by BBO conversion from 532 nm to 266 nm. The green-to-UV conversion efficiency reaches 7.14%, enabling stable and efficient deep ultraviolet pulsed laser output. In the experiment, an AOM acousto-optic modulator was employed for pulse modulation. The dual-end pumping structure effectively enhanced pumping efficiency and improved thermal management performance. The entire system demonstrated excellent compactness, output stability, and beam quality.\u003c/p\u003e\u003cp\u003eThrough systematic component selection and optical path optimization, this paper demonstrates the feasibility and practicality of a deep ultraviolet laser system based on an all-solid-state laser and out-of-cavity frequency doubling technology. This watt-level low-noise laser holds promising applications in material microfabrication, deep ultraviolet lithography, and biological detection. Future work may focus on enhancing beam quality, optimizing thermal management structures, and improving module integration to achieve industrial applications with higher power and repetition rates.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eX. wrote the main manuscript text and L. prepared figures 2-3. All authors reviewed the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eCai, B.Y., Mao, X., Hou, H., et al.: Double-pulse laser ablation sampling: Enhancement of analyte emission by a second laser pulse at 213 nm. Spectrochim Acta B Spectrosc. \u003cb\u003e110\u003c/b\u003e, 51\u0026ndash;55 (2015)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChaitanya Kumar, S., Canals Casals, J., Sanchez Bautista, E., et al.: Yb-fiber-laser-based, 1.8 W average power, picosecond ultraviolet source at 266 nm. Opt. Lett. \u003cb\u003e40\u003c/b\u003e(10), 2397\u0026ndash;2400 (2015)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFang, Z., Hou, Z., Yang, F., et al.: High-efficiency UV generation at 266 nm in a new nonlinear optical crystal NaSr₃Be₃B₃O₉F₄. Opt. Express. \u003cb\u003e25\u003c/b\u003e(22), 26500\u0026ndash;26507 (2017)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKuryak, A.N., Tikhomirov, B.A.: Role of water vapour in the absorption of nanosecond 266-nm laser pulses by atmospheric air. Quantum Electron. \u003cb\u003e50\u003c/b\u003e(9), 876 (2020)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLi, X., Wang, Z., Fu, Y., et al.: Wavelength dependence in the analysis of carbon content in coal by nanosecond 266 nm and 1064 nm laser induced breakdown spectroscopy. Plasma Sci. Technol. \u003cb\u003e17\u003c/b\u003e(8), 621 (2015)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eOrii, Y., Kohno, K., Tanaka, H., et al.: Stable 10,000-hour operation of 20-W deep ultraviolet laser generation at 266 nm. Opt. Express. \u003cb\u003e30\u003c/b\u003e(7), 11797\u0026ndash;11808 (2022)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePascu, M.L., Danko, B., Martins, A., et al.: Exposure of chlorpromazine to 266 nm laser beam generates new species with antibacterial properties: contributions to development of a new process for drug discovery. PLoS One \u003cb\u003e8\u003c/b\u003e(2), e55767 (2013)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRao, A.S., Chaitanya, N.A., Samanta, G.K.: High-power, high repetition-rate, ultrafast fibre laser based source of DUV radiation at 266 nm. OSA Contin. \u003cb\u003e2\u003c/b\u003e(1), 99\u0026ndash;106 (2018)\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"All-solid-state laser, Out-cavity frequency doubling, 266 nm deep ultraviolet, Pulse, Beam quality","lastPublishedDoi":"10.21203/rs.3.rs-7565380/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7565380/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis paper addresses the demand for wafer-level low-noise deep ultraviolet lasers in precision machining and spectral detection fields by designing and constructing an all-solid-state 532 nm green light and 266 nm deep ultraviolet laser system. The system employs a BBO crystal as the frequency-doubling crystal, achieving efficient conversion of 532 nm green light to 266 nm deep ultraviolet light via external-cavity frequency-doubling technology. Experimental results demonstrate that at a 20 kHz repetition rate, the system outputs laser pulses with a width of 11 ns. The 532 nm laser achieves a peak power of 14 W, while the 266 nm deep ultraviolet laser delivers watt-level output (peak power 1 W). Both lasers exhibit excellent beam quality (M\u0026sup2;x\u0026thinsp;=\u0026thinsp;1.25, M\u0026sup2;y\u0026thinsp;=\u0026thinsp;1.15) and low noise characteristics, meeting the demands of high-stability applications.\u003c/p\u003e","manuscriptTitle":"Wafer-scale Low-Noise 266 nm Deep Ultraviolet All-Solid-State Laser","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-22 14:58:26","doi":"10.21203/rs.3.rs-7565380/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"4c75b171-1ea7-4264-91e1-95140d6217ca","owner":[],"postedDate":"October 22nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-11-11T02:53:53+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-22 14:58:26","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7565380","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7565380","identity":"rs-7565380","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}