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arXiv · 2308.11367

Non-Hermitian topological ohmmeter

Viktor Könye·Kyrylo Ochkan·Anastasiia Chyzhykova·Jan Carl Budich·Jeroen van den Brink·Ion Cosma Fulga·Joseph Dufouleur
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Abstract

Measuring large electrical resistances forms an essential part of common applications such as insulation testing, but suffers from a fundamental problem: the larger the resistance, the less sensitive a canonical ohmmeter is. Here we develop a conceptually different electronic sensor by exploiting the topological properties of non-Hermitian matrices, whose eigenvalues can show an exponential sensitivity to perturbations. The ohmmeter is realized in an multi-terminal, linear electric circuit with a non-Hermitian conductance matrix, where the target resistance plays the role of the perturbation. We inject multiple currents and measure a single voltage in order to directly obtain the value of the resistance. The relative accuracy of the device increases exponentially with the number of terminals, and for large resistances outperforms a standard measurement by over an order of magnitude. Our work paves the way towards leveraging non-Hermitian conductance matrices in high-precision sensing.

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Viktor Könye, Kyrylo Ochkan, Anastasiia Chyzhykova, Jan Carl Budich, Jeroen van den Brink, Ion Cosma Fulga, Joseph Dufouleur. 2023-08-22. Non-Hermitian topological ohmmeter. https://doi.org/10.1103/physrevapplied.22.l031001

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