Superpositions in Atomic Quantum Rings

TL;DR

This paper demonstrates how optical coherent state superpositions can induce superpositions of flux tubes in atomic quantum rings, leading to superpositions of counter-rotating atomic states in ring and harmonic traps.

Contribution

It introduces a novel method using light-induced gauge potentials with coherent state superpositions to create superpositions of flux tubes affecting trapped atoms.

Findings

Ground state is a superposition of counter-rotating states.

Superpositions occur in both ring and harmonic trapping geometries.

Method enables new quantum control of atomic states.

Abstract

Ultracold atoms are trapped circumferentially on a ring that is pierced at its center by a flux tube arising from a light-induced gauge potential due to applied Laguerre-Gaussian fields. We show that by using optical coherent state superpositions to produce light-induced gauge potentials, we can create a situation in which the trapped atoms are simultaneously exposed to two distinct flux tubes, thereby creating superpositions in atomic quantum rings. We consider the examples of both a ring geometry and harmonic trapping, and in both cases the ground state of the quantum system is shown to be a superposition of counter-rotating states of the atom trapped on the two distinct flux tubes.