超越旋波近似的自旋轨道耦合拓扑费米子  

Topological spin-orbit-coupled fermions beyond rotating wave approximation

作　　者：张涵 王文伟 乔畅 张龙 梁明诚 吴瑞 王旭杰 刘雄军 张熙博 Han Zhang;Wen-Wei Wang;Chang Qiao;Long Zhang;Ming-Cheng Liang;Rui Wu;Xu-Jie Wang;Xiong-Jun Liu;Xibo Zhang(International Center for Quantum Materials,School of Physics,Peking University,Beijing 100871,China;Collaborative Innovation Center of Quantum Matter,Beijing 100871,China;School of Physics and Institute for Quantum Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China;Hefei National Laboratory,Hefei 230088,China;Beijing Academy of Quantum Information Sciences,Beijing 100193,China;International Quantum Academy,Shenzhen 518048,China)

机构地区：[1]International Center for Quantum Materials,School of Physics,Peking University,Beijing 100871,China [2]Collaborative Innovation Center of Quantum Matter,Beijing 100871,China [3]School of Physics and Institute for Quantum Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China [4]Hefei National Laboratory,Hefei 230088,China [5]Beijing Academy of Quantum Information Sciences,Beijing 100193,China [6]International Quantum Academy,Shenzhen 518048,China

出　　处：《Science Bulletin》2024年第6期747-755,共9页科学通报（英文版）

基　　金：supported by the Chinese Academy of Sciences Strategic Priority Research Program(XDB35020100);the National Key Research and Development Program of China(2021YFA1400900 and 2018YFA0305601);the National Natural Science Foundation of China(11874073,12304564,11825401,12204187,12261160368);the Open Project of Shenzhen Institute of Quantum Science and Engineering(SIQSE202003);the Hefei National Laboratory;the Scientific and Technological Innovation 2030 Key Program of Quantum Communication and Quantum Computing(2021ZD0301903 and 2021ZD0302000)。

摘　　要：The realization of spin-orbit-coupled ultracold gases has driven a wide range of research and is typically based on the rotating wave approximation(RWA).By neglecting the counter-rotating terms,RWA characterizes a single near-resonant spin-orbit(SO)coupling in a two-level system.Here,we propose and experimentally realize a new scheme for achieving a pair of two-dimensional(2D)SO couplings for ultracold fermions beyond RWA.This work not only realizes the first anomalous Floquet topological Fermi gas beyond RWA,but also significantly improves the lifetime of the 2D-SO-coupled Fermi gas.Based on pump-probe quench measurements,we observe a deterministic phase relation between two sets of SO couplings,which is characteristic of our beyond-RWA scheme and enables the two SO couplings to be simultaneously tuned to the optimum 2D configurations.We observe intriguing band topology by measuring two-ring band-inversion surfaces,quantitatively consistent with a Floquet topological Fermi gas in the regime of high Chern numbers.Our study can open an avenue to explore exotic SO physics and anomalous topological states based on long-lived SO-coupled ultracold fermions.

关 键 词：Spin-orbit coupling Ultracold atoms Fermi gases Quantum simulation Topological phases of matter 

分 类 号：O469[理学—凝聚态物理]