Two-dimensional Quantum Droplets under an Inhomogeneous Synthetic Gauge Field

Sheng-Pin Chang^1*, Che-Hsiu Hsueh², Wen-Chin Wu²

¹Institute of Physics, National Yang Ming Chiao Tung University, Hsinchu, Taiwan
²Department of Physics, National Taiwan Normal University, Taipei, Taiwan

* Presenter:Sheng-Pin Chang, email:s44930e0@gmail.com

Quantum droplet (QD), a self-bound state, is a novel state in binary Bose-Einstein condensates (BECs) when two-body attractive and repulsive interactions balance each other, and when higher-order Lee-Huang-Yang (LHY) correction is considered. In this paper, we report a study of quasi-two-dimensional QDs, which are under an inhomogeneous, high-gradient, gauge field, generated from an optical laser field. Our simulations show that the gauge field can cause linear vortex lattice to form in the center of QD. Based on the Thomas-Fermi approximation, we derived an equation for the number of vortices, N, and how N depends on the size of QD and other parameters related to the gauge filed is explicitly revealed. The equation collaborates well with the results of simulation. We have also considered a model in which two laser fields in different directions superimpose to create a potential well. In this case, double-linear vortex lattice can form in the QDs.

Keywords: Bose-Einstein condensates, Gauge Fields, Quantum Droplet