Thermal Phase Transitions of Strongly Correlated Bosons with Spin-Orbit Coupling

TL;DR

This paper investigates how thermal fluctuations affect stripe superfluid states in strongly correlated two-component bosons with spin-orbit coupling, revealing a two-step melting process and an intermediate normal fluid phase.

Contribution

It introduces a finite temperature Gutzwiller approach to study thermal phase transitions in a spin-orbit coupled bosonic lattice model, highlighting the melting of stripe superfluid states.

Findings

Thermal fluctuations cause a two-step melting of stripe superfluid states.

An intermediate normal fluid phase with stripe order exists during melting.

The study provides insights into thermal effects in spin-orbit coupled bosonic systems.

Abstract

Experiments on ultracold atomic gases have begun to explore lattice effects and thermal fluctuations for two-component bosons with spin-orbit coupling (SOC). Motivated by this, we study a $tJ$ model of strongly correlated lattice bosons, with equal Rashba-Dresselhaus SOC and a uniform magnetic field. At zero temperature, a Gutzwiller ansatz is shown to capture lattice variants of stripe superfluid (SF) ground states. We formulate a finite temperature generalization of the Gutzwiller approach and show that thermal fluctuations in the doped Mott insulator drive a two-step melting of the stripe SF, revealing a wide intermediate regime of a normal fluid with stripe order.