2025/07/07 by Mateusz Szurek, Szurek, Mateusz, Cheng, Hanqiao +5
Materials Science · Physics and Astronomy · #Electronic and Structural Properties of Oxides #Quantum and electron transport phenomena #Surface and Thin Film Phenomena
paper · pdf · doi:10.48550/arxiv.2507.05481
In materials known as failed insulators, electrical resistivity increases as temperature decreases, yet does not diverge - a phenomenon inconsistent with single-particle theories. We investigate the origin of this behavior by measuring shot noise in nanojunctions of nitrogen-doped beta-Ta, a prototypical failed insulator. Junctions as short as 8 nanometers exhibit hot-electron shot noise, indicating strong electron interactions. We show that charge hopping mediated by these interactions explains the anomalous electronic properties. Our findings open new avenues for exploiting electron interactions in spin-orbitronic and superconducting applications of failed insulators.