Revealing inherent quantum interference and entanglement of a Dirac Fermion

Revealing inherent quantum interference and entanglement of a Dirac Fermion | 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 Revealing inherent quantum interference and entanglement of a Dirac Fermion Wen Ning, Ri-Hua Zheng, Yan Xia, Kai Xu, Hekang Li, Dongning Zheng, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-2921505/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 10 Oct, 2023 Read the published version in npj Quantum Information → Version 1 posted 12 You are reading this latest preprint version Abstract The Dirac equation is critical to understanding the universe, and plays an important role in technological advancements. Compared to the stationary solution, the dynamical evolution under the Dirac Hamiltonian is less understood, exemplified by Zitterbewegung. Although originally predicted in relativistic quantum mechanics, Zitterbewegung can also appear in some classical systems, which leads to the important question of whether Zitterbewegung of Dirac Fermions is underlain by a more fundamental and universal interference behavior without classical analogs. We here reveal such an interference pattern in phase space, which underlies but goes beyond Zitterbewegung, and whose nonclassicality is manifested by the negativity of the phase-space quasiprobability distribution, and the associated pseudospin-momentum entanglement. We confirm this discovery by numerical simulation and an on-chip experiment, where a superconducting qubit and a quantized microwave field respectively emulate the internal and external degrees of freedom of a Dirac particle. The measured quasiprobability negativities well agree with the numerical simulation. Besides being of fundamental importance, the demonstrated nonclassical effects are useful in quantum technology. Physical sciences/Physics/Quantum physics/Quantum simulation Physical sciences/Physics/Quantum physics/Qubits Full Text Additional Declarations (Not answered) Supplementary Files SI.pdf Cite Share Download PDF Status: Published Journal Publication published 10 Oct, 2023 Read the published version in npj Quantum Information → Version 1 posted Editorial decision: revise 18 Jul, 2023 Review # 3 received at journal 13 Jul, 2023 Review # 2 received at journal 30 Jun, 2023 Reviewer # 3 agreed at journal 11 Jun, 2023 Reviewer # 2 agreed at journal 07 Jun, 2023 Review # 1 received at journal 28 May, 2023 Reviewer # 1 agreed at journal 15 May, 2023 Reviewers invited by journal 14 May, 2023 Submission checks completed at journal 09 May, 2023 First submitted to journal 05 May, 2023 Unknown event 05 May, 2023 Editor assigned by journal 04 May, 2023 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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