Practical scheme for a light-induced gauge field in an atomic Bose gas

TL;DR

This paper presents a practical method to create an Abelian gauge field in an atomic Bose gas using laser beams, enabling vortex formation without significant heating, applicable to alkali-metal atoms.

Contribution

It introduces a scheme to generate gauge fields in atomic gases that remains effective at large detuning, reducing heating and enabling vortex lattice formation.

Findings

The scheme produces a gauge field inducing vortices in Bose gases.

Numerical simulations confirm vortex lattice formation under the proposed scheme.

The method is applicable to alkali-metal atoms with minimal spontaneous emission.

Abstract

We propose a scheme to generate an Abelian gauge field in an atomic gas using two crossed laser beams. If the internal atomic state follows adiabatically the eigenstates of the atom-laser interaction, Berry's phase gives rise to a vector potential that can nucleate vortices in a Bose gas. The present scheme operates even for a large detuning with respect to the atomic resonance, making it applicable to alkali-metal atoms without significant heating due to spontaneous emission. We test the validity of the adiabatic approximation by integrating the set of coupled Gross-Pitaevskii equations associated with the various internal atomic states, and we show that the steady state of the interacting gas indeed exhibits a vortex lattice, as expected from the adiabatic gauge field.