Supersymmetry-like tunneling current noise as a probe of Goldstino excitation in a Bose-Fermi mixture

TL;DR

This paper proposes using tunneling current noise, specifically the Fano factor, as a probe to detect Goldstino excitations in a Bose-Fermi mixture, revealing a crossover from quasiparticle to multiparticle transport.

Contribution

It introduces a theoretical method to detect Goldstino modes via shot noise analysis in ultracold Bose-Fermi mixtures, highlighting the role of the Fano factor in identifying supersymmetry breaking.

Findings

Fano factor varies with density, indicating a crossover in transport mechanisms.

Tunneling channel can be controlled by tuning the potential barrier.

Goldstino excitation influences the noise characteristics of the tunneling current.

Abstract

The Goldstino, which is a fermionic Nambu-Goldstone mode, has been predicted in a Bose-Fermi mixture when the supersymmetry is broken. To detect this excitation mode, we theoretically investigate the shot noise of the supersymmetry-like tunneling current in a weakly interacting ultracold Bose-Fermi mixture. The Fano factor, which is defined by the noise-to-current ratio, reflect the elementary carriers of the tunneling process. The change of the Fano factor microscopically as the density changes evinces a crossover from the quasiparticle transport to multiparticle (Goldstino) transport. The tunneling channel can also be changed by tuning the potential barrier.