Anomalous shot noise in a bad metal β-tantalum

Abstract

We investigate the electronic shot noise produced by nanowires of β-Ta, an archetypal “bad” metal with resistivity near the Ioffe–Regel localization limit. The Fano factor characterizing the shot noise exhibits a strong dependence on temperature and is suppressed compared to the expectations for quasiparticle diffusion, but hopping transport is ruled out by the analysis of scaling with the nanowire length. These anomalous behaviors closely resemble those of strange metal nanowires, suggesting that β-Ta may host a correlated electron liquid. This material provides an accessible platform for exploring exotic electronic states of matter.