Robust Mesoscopic Superposition of Strongly Correlated Ultracold Atoms

TL;DR

This paper presents a method to generate and detect robust mesoscopic superpositions of strongly correlated ultracold atoms in a ring trap, with potential for large particle numbers and resilience against particle loss.

Contribution

It introduces a scheme to create mesoscopic superpositions in strongly interacting bosonic systems that are more scalable and robust than previous weakly interacting approaches.

Findings

Superposition states are robust against single-particle loss.

Coupling scales favorably with large particle numbers.

Time-dependent parameters can detect superpositions via coherent oscillations.

Abstract

We propose a scheme to create coherent superpositions of annular flow of strongly-interacting bosonic atoms in a 1D ring trap. The non-rotating ground state is coupled to a vortex state with mesoscopic angular momentum by means of a narrow potential barrier and an applied phase that originates from either rotation or a synthetic magnetic field. We show that superposition states in the Tonks-Girardeau regime are robust against single-particle loss due to the effects of strong correlations. The coupling between the mesoscopically distinct states scales much more favorably with particle number than in schemes relying on weak interactions, thus making particle numbers of hundreds or thousands feasible. Coherent oscillations induced by time variation of parameters may serve as a 'smoking gun' signature for detecting superposition states.