Four-body Efimov effect

TL;DR

This paper predicts a specific mass ratio range where a novel four-body Efimov effect occurs, resulting in weakly bound tetramers without the formation of Efimov trimers, expanding understanding of few-body quantum phenomena.

Contribution

It introduces the first prediction of a four-body Efimov effect in a specific mass ratio interval for three identical fermions and one distinguishable particle.

Findings

Identifies the mass ratio interval 13.384 < M/m < 13.607 for the four-body Efimov effect.

Predicts the existence of weakly bound tetramers without Efimov trimers.

Expands the theoretical understanding of few-body quantum states in ultracold gases.

Abstract

We study three same spin state fermions of mass M interacting with a distinguishable particle of mass m in the unitary limit where the interaction has a zero range and an infinite s-wave scattering length. We predict an interval of mass ratio 13.384 < M/m < 13.607 where there exists a purely four-body Efimov effect, leading to the occurrence of weakly bound tetramers without Efimov trimers.