华东师范大学学报（自然科学版） >

2024 , Vol. 2024 >Issue 3: 64 - 72

DOI: https://doi.org/10.3969/j.issn.1000-5641.2024.03.007

原子、分子和光物理

自旋扭曲光晶格中的玻色-爱因斯坦凝聚体

  • 王美玲 ,
  • 左承毅 ,
  • 李燕
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  • 华东师范大学 物理与电子科学学院, 上海　200241

收稿日期: 2023-04-11

  网络出版日期: 2024-05-25

基金资助

重庆市自然科学基金 (CSTB2022NSCQ-MSX0585)

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Bose-Einstein condensates in spin-twisted optical lattices

  • Meiling WANG ,
  • Chengyi ZUO ,
  • Yan LI
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  • School of Physics and Electronic Science, East China Normal University, Shanghai　200241, China

Received date: 2023-04-11

  Online published: 2024-05-25

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摘要

研究了自旋依赖双层方形光晶格中玻色-爱因斯坦凝聚体(Bose-Einstein condensates, BEC)的基态特征. 双层晶格间的相对扭曲角度和层间耦合强度是影响超冷原子密度分布的重要可调参数. 当光晶格的最低能带呈单阱色散时, 超冷原子在莫尔晶格(Moiré lattice)中的局域化受扭曲角度、层间耦合强度、原子数和晶格深度等的影响; 当光晶格的最低能带呈双阱色散时, 光晶格的扭曲可导致2个自旋态的反向扭曲, 随着层间耦合强度的增加, 2个扭曲的自旋态逐渐重合. 该研究工作有助于深入探索扭曲光晶格超冷原子中的新奇量子效应.

关键词： 玻色-爱因斯坦凝聚体; 扭曲角度; 层间耦合; 自旋扭曲光晶格

本文引用格式

王美玲 , 左承毅 , 李燕 . 自旋扭曲光晶格中的玻色-爱因斯坦凝聚体[J]. 华东师范大学学报（自然科学版）, 2024 , 2024(3) : 64 -72 . DOI: 10.3969/j.issn.1000-5641.2024.03.007

Abstract

The characteristics of the ground states of Bose-Einstein condensates (BEC) in spin-dependent bilayer square optical lattices are investigated in this paper. The relative twist angle between the two lattices and the interlayer coupling strength are the main tunable parameters that affect the density distribution of the ultracold atoms. When the lowest band of the lattices exhibits a single-well dispersion, the localization of the ultracold atoms in the Moiré lattice can be determined from the twist angle, interlayer coupling strength, number of atoms, and lattice depth. When the lowest band of the lattices exhibits a double-well dispersion, the twist between the lattices leads to the twist of the two spin states. With an increase in interlayer coupling strength, the two twisted spin states will overlap. The results of this work will stimulate further exploration of novel quantum effect with ultracold atoms in twisted optical lattices.

Key words： Bose-Einstein condensates; twist angle; interlayer coupling; spin-twisted optical lattices

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