Sigature of the universal super Efimov Effect: three-body contact in two dimensional Fermi gases

TL;DR

This paper introduces a new three-body contact quantity in 2D Fermi gases to detect the universal super Efimov effect, linking few-body physics to many-body observable phenomena.

Contribution

It proposes the three-body contact $C_\theta$ as a thermodynamic measure to identify the super Efimov effect in many-body systems.

Findings

$C_\theta$ influences RF spectrum, momentum distribution, and atom loss rate.

Signature of super Efimov effect can be detected via three-body contact.

Provides a bridge between few-body universal physics and many-body observables.

Abstract

A new class of universal "three-body" bound states has been recently predicted theoretically for identical fermions interacting at p-wave resonance in two dimensions. This phenomenon is called the super Efimov effect since the binding energies of the states follow a intriguing double exponential scaling. However, experimental resolution of this scaling is expected to meet formidable challenges. In this work, we introduce a new thermodynamic quantity, the three-body contact $C_\theta$, to quantify three-body correlations in a two dimensional gas composed of the resonantly interacting fermions; the contact $C_\theta$ is the consequence of the underlying universal super Efimov effect in the many-body context. We show how $C_\theta$ affects physical observables such as the radio-frequency spectrum, the momentum distribution and the atom loss rate. Signature of the elusive super Efimov effect in the thermodynamic system can be pinned down by the detection of the three-body contact $C_\theta$ via these observables.