Uniformly frustrated bosonic Josephson-junction arrays

TL;DR

This paper derives a model for 2D bosonic Josephson-junction arrays with rotation, revealing complex vortex patterns through simulations, influenced by harmonic trapping and optical lattice effects.

Contribution

It introduces a uniformly frustrated XY model for rotating Bose-Einstein condensates in optical lattices with nonuniform coupling due to harmonic trapping.

Findings

Rich vortex patterns depend on the frustration parameter

Harmonic trap causes nonuniform coupling in the model

Monte Carlo simulations reveal diverse ground states

Abstract

We derive a uniformly frustrated $XY$ model that describes two-dimensional Josephson-junction arrays consisting of rotating Bose-Einstein condensates trapped by both a harmonic trap and a corotating deep optical lattice. The harmonic trap makes the coupling constant of the model have a nonuniform parabolic dependance. We study the ground state through Monte Carlo simulations in a wide range of the frustration parameter $f$, revealing a rich variety of vortex patterns.