Superfluidity breakdown of Rabi-coupled two-component Bose-Einstein condensates in optical lattices

TL;DR

This paper investigates the stability of superfluids in Rabi-coupled two-component Bose-Einstein condensates within optical lattices, revealing how Rabi coupling influences superfluid stability and identifying regimes of instability.

Contribution

It provides a detailed analysis of superfluid stability regimes and demonstrates the stabilizing effect of Rabi coupling in optical lattice setups.

Findings

Rabi coupling can stabilize superfluids in optical lattices.

Distinct regimes of Landau and dynamical instabilities are identified.

Separation between Landau and dynamical instabilities is significant in Zeeman lattices.

Abstract

We demarcate the unstable regimes of superfluids in a Rabi-coupled two-component Bose-Einstein condensate in the presence of optical lattices. We find that the Rabi coupling can stabilize superfluids. A significant separation between Landau and dynamical instabilities is presented in a Rabi-coupled Zeeman lattice.