Quantum droplet of one-dimensional bosons with a three-body attraction

TL;DR

This paper explores one-dimensional bosonic systems with purely three-body attractions, revealing universal few-body bound states and a many-body droplet whose energy grows exponentially with particle number, with potential realization in optical lattices.

Contribution

It demonstrates the formation of universal few-body bound states and a many-body droplet driven solely by three-body interactions in 1D bosons, a novel regime in ultracold atom physics.

Findings

Universal binding energies for few-body states

Exponential growth of droplet energy with particle number

Potential realization with coupled two-component bosons in optical lattices

Abstract

Ultracold atoms offer valuable opportunities where interparticle interactions can be controlled at will. In particular, by extinguishing the two-body interaction, one can realize unique systems governed by the three-body interaction, which is otherwise hidden behind the two-body interaction. Here we study one-dimensional bosons with a weak three-body attraction and show that they form few-body bound states as well as a many-body droplet stabilized by the quantum mechanical effect. Their binding energies relative to that of three bosons are all universal and the ground-state energy of the dilute droplet is found to grow exponentially as $E_N/E_3\to\exp(8N^2/\sqrt3\pi)$ with increasing particle number $N\gg1$. The realization of our system with coupled two-component bosons in an optical lattice is also discussed.