Stability of small amplitude normal modes of a Bose-Einstein condensate with a singly quantized vortex confined in an optical lattice

TL;DR

This paper investigates how optical lattices influence the stability of a singly quantized vortex in a Bose-Einstein condensate, revealing that sufficient lattice depth can stabilize the vortex depending on interaction strength.

Contribution

It demonstrates that optical lattices can stabilize vortex modes in BECs and identifies the critical lattice depth needed for stability based on interaction parameters.

Findings

Optical lattices stabilize vortex modes in BECs.

A critical lattice depth depends on the interaction strength.

2-D lattices are less effective in stabilizing vortices than 1-D lattices.

Abstract

We study the dynamics of a BEC with a singly quantized vortex, placed in the combined potential of a 1-D (2-D) optical lattice and an axi-symmetric harmonic trap. A time-dependent variational Lagrangian analysis shows that an optical lattice helps to stabilize the vortex which in absence of the optical lattice is unstable. We find that the normal modes are stable only if the depth of the optical potential is more than a certain critical value. This critical value of the optical potential depends on the interaction parameter.In general higher the interaction parameter,lower the value of the optical potential required to stabilize the vortex. The BEC with the singly quantized vortex is found to be relatively more unstable in a 2-D optical lattice compared to a 1-D optical lattice.