Quantum Droplets in Two-Dimensional Bose Mixtures at Finite Temperature

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.Received 20 May 2024Accepted 18 July 2024DOI:https://doi.org/10.1103/PhysRevLett.133.083401© 2024 American Physical SocietyPhysics Subject Headings (PhySH)Research AreasBose gasesBose-Bose mixturesSuperfluid densityPhysical Systems2-dimensional systemsSuperfluidsTechniquesPath-integral Monte CarloAtomic, Molecular & Optical