arXiv:2403.14524 · Physical review. B./Physical review. B

Probing the goldstino excitation through tunneling transport in a Bose-Fermi mixture with explicitly broken supersymmetry

Tingyu Zhang, Yixin Guo, Hiroyuki Tajima, Haozhao Liang

Published Aug 22, 2024• 6 citations

Abstract

We theoretically investigate the tunneling transport in a repulsively interacting ultracold Bose-Fermi mixture. A two-terminal model is applied to such a mixture, and the supersymmetry-like tunneling current through the junction can be induced by the bias of the fermion chemical potential between two reservoirs. The goldstino, which is the Nambu-Goldstone fermionic mode associated with the spontaneous sypersymmetry breaking and appears as a gapped mode in the presence of the explicit supersymmetry breaking in existing Bose-Fermi mixtures, is found to contribute to the tunneling transport as a supercharge exchanging process. Our study provides a potential way to detect the goldstino transport in cold atom experiments.

DOI: 10.1103/physrevb.110.064512

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