Quantum Bose-Fermi droplets

TL;DR

This paper investigates the formation and stability of self-bound quantum droplets in a zero-temperature Bose-Fermi mixture, highlighting the role of higher order corrections and discussing experimental challenges.

Contribution

It introduces the concept of quantum Bose-Fermi droplets stabilized by higher order interactions, expanding the understanding of self-bound quantum fluids.

Findings

Higher order corrections enable droplet formation

Numerical simulations confirm stability of finite droplets

Main obstacle is inelastic three-body collisions

Abstract

We study the stability of a zero temperature mixture of attractively interacting degenerate bosons and spin-polarized fermions in the absence of confinement. We demonstrate that higher order corrections to the standard mean-field energy can lead to a formation of Bose-Fermi liquid droplets -- self-bound systems in three-dimensional space. The stability analysis of the homogeneous case is supported by numerical simulations of finite systems by explicit inclusion of surface effects. We discuss the experimental feasibility of formation of quantum droplets and indicate the main obstacle -- inelastic three-body collisions.