Optimal scaling of persistent currents for interacting bosons on a ring

TL;DR

This paper investigates how the amplitude of persistent currents in interacting bosonic atoms on a ring scales with system size, revealing optimal scaling at intermediate interaction strengths through analytical and numerical methods.

Contribution

It identifies the optimal interaction regime for persistent current scaling in bosonic rings, combining analytical and numerical analysis across interaction regimes.

Findings

Power-law scaling in the strongly interacting regime

Optimal scaling occurs at intermediate interactions

Scaling behavior aligns with Luttinger-liquid theory predictions

Abstract

We consider the persistent currents induced by an artificial gauge field applied to interacting ultra-cold bosonic atoms in a tight ring trap. Using both analytical and numerical methods, we study the scaling of the persistent current amplitude with the size of the ring. In the strongly interacting regime we find a power-law scaling, in good agreement with the predictions of the Luttinger-liquid theory. By exploring all interaction regimes we find that the scaling is optimal, i.e. the current amplitude decreases slower with the system size, at intermediate interactions.