Non-Hermitian topological ohmmeter
Viktor Könye, Kyrylo Ochkan, Anastasiia Chyzhykova, Jan Carl Budich, Jeroen van den Brink, Ion Cosma Fulga, Joseph Dufouleur
Abstract
Measuring large electrical resistances is an essential part of common applications such as insulation testing, but it suffers from a fundamental problem: The larger the resistance, the less sensitive a canonical ohmmeter is. Here the authors use the topological properties of non-Hermitian matrices to design a multiple-current-source electrical circuit that functions as a highly precise ohmmeter. Both the sensitivity of the device and its signal-to-noise ratio increase exponentially as more and more current sources are included in the circuit, paving the way toward overcoming the intrinsic limitations of currently available measurement devices.