Nonlinear localization of ultracold atomic Fermi gas in moiré optical lattices  

作　　者：Xiuye Liu Jianhua Zeng 

机构地区：[1]Xi’an Institute of Optics and Precision Mechanics of Chinese Academy of Sciences,Center for Attosecond Science and Technology,State Key Laboratory of Transient Optics and Photonics,Xi’an,China [2]University of Chinese Academy of Sciences,Beijing,China [3]Shanxi University,Collaborative Innovation Center of Extreme Optics,Taiyuan,China

出　　处：《Advanced Photonics Nexus》2024年第3期50-57,共8页先进光子学通讯（英文）

基　　金：supported by the National Natural Science Foundation of China(Grant No.12074423);the Young Scholar of Chinese Academy of Sciences in Western China(Grant No.XAB2021YN18);the Provincial Science Fund for Distinguished Young Scholars of Shaanxi(Grant No.2024JC-JCQN-11);the China Postdoctoral Science Foundation(Grant No.2023M733722);the Postdoctoral Fellowship Program of CPSF(Grant No.GZC20232947).

摘　　要：Moirésuperlattices,a twisted functional structure crossing the periodic and nonperiodic potentials,have recently attracted great interest in multidisciplinary fields,including optics and ultracold atoms,because of their unique band structures,physical properties,and potential implications.Driven by recent experiments on quantum phenomena of bosonic gases,the atomic Bose–Einstein condensates in moiréoptical lattices,by which other quantum gases such as ultracold fermionic atoms are trapped,could be readily achieved in ultracold atom laboratories,whereas the associated nonlinear localization mechanism remains unexploited.Here,we report the nonlinear localization theory of ultracold atomic Fermi gases in two-dimensional moiréoptical lattices.The linear Bloch-wave spectrum of such a twisted structure exhibits rich nontrivial flat bands,which are separated by different finite bandgaps wherein the existence,properties,and dynamics of localized superfluid Fermi gas structures of two types,gap solitons and gap vortices(topological modes)with vortex charge S¼1,are studied numerically.Our results demonstrate the wide stability regions and robustness of these localized structures,opening up a new avenue for studying soliton physics and moiréphysics in ultracold atoms beyond bosonic gases.

关 键 词：moiréoptical lattices gap solitons ultracold Fermi gases density-functional equation. 

分 类 号：O56[理学—原子与分子物理]