Wannier solitons in spin-orbit-coupled Bose-Einstein condensates in optical lattices with a flat band
Year: 2023
Type: article
Abstract: We investigate families of soliton solutions in a spin-orbit-coupled Bose-Einstein condensate embedded in an optical lattice, which bifurcate from the nearly flat lowest band. Unlike the conventional gap solitons, the obtained solutions have the shape well approximated by a Wannier function (or a few Wannier functions) of the underlying linear Hamiltonian with amplitudes varying along the family and with nearly constant widths. The Wannier solitons sharing all symmetries of the system Hamiltonian are found to be stable. Such solutions allow for the construction of Wannier breathers that can be viewed as nonlinearly coupled one-hump solitons. The breathers are well described by a few-mode model and manifest stable behavior either in an oscillatory regime with balanced average populations or in a self-trapping regime characterized by unbalanced atomic populations of the local potential minima (similarly to the conventional boson Josephson junction), with the frequencies controlled by the interatomic interactions.
Source: Physical Review A
Authors: Chenhui Wang, Yongping Zhang, V. V. Konotop
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4383815682