Quantum droplets in two-dimensional Bose mixtures at finite temperature

TL;DR

This paper studies the formation and properties of quantum droplets in two-dimensional Bose mixtures at finite temperature using Monte Carlo simulations, revealing phase transitions, equation of state, and superfluid behavior.

Contribution

It provides the first detailed finite-temperature analysis of quantum droplets in 2D Bose mixtures, including phase transition critical points and superfluid response.

Findings

Quantum droplets form at finite temperature in 2D Bose mixtures.

The equation of state and phase coexistence are characterized.

Superfluid response appears abruptly at the gas-liquid transition.

Abstract

We investigate the formation of quantum droplets at finite temperature in attractive Bose mixtures subject to a strong transverse harmonic confinement. By means of exact path-integral Monte Carlo methods we determine the equilibrium density of the gas and the liquid as well as the pressure vs. volume dependence along isothermal curves. Results for the equation of state and for the gas-liquid coexistence region in quasi-2D configurations are compared with calculations in strictly two dimensions, finding excellent agreement. Within the pure 2D model we explore the relevance of the quantum scale anomaly and we determine the critical interaction strength for the occurrence of the first-order gas to liquid transition. Furthermore, we find that the superfluid response develops suddenly, following the density jump from the gas to the liquid state.