AC-induced superfluidity

TL;DR

This paper demonstrates that ultracold bosonic atoms in a tilted optical lattice can exhibit superfluidity when driven by resonant AC forcing, enabling the creation of condensates with negative effective mass, supported by simulations and Floquet theory.

Contribution

It introduces a novel method to induce superfluidity in ultracold atoms using resonant AC forcing and provides a theoretical framework for understanding this phenomenon.

Findings

Superfluidity can be induced by resonant AC forcing in tilted optical lattices.

A Bose-Einstein condensate with negative effective mass can be prepared.

The results are supported by numerical simulations and Floquet-Fock state analysis.

Abstract

We argue that a system of ultracold bosonic atoms in a tilted optical lattice can become superfluid in response to resonant AC forcing. Among others, this allows one to prepare a Bose-Einstein condensate in a state associated with a negative effective mass. Our reasoning is backed by both exact numerical simulations for systems consisting of few particles, and by a theoretical approach based on Floquet-Fock states.