Bose-Einstein condensates in spin-twisted optical lattices

doi:10.3969/j.issn.1000-5641.2024.03.007

Abstract

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

CLC Number:

O431.2

Meiling WANG, Chengyi ZUO, Yan LI. Bose-Einstein condensates in spin-twisted optical lattices[J]. Journal of East China Normal University(Natural Science), 2024, 2024(3): 64-72.

Figures/Tables 7

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