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arXiv · 2402.04207

Detector-tuned overlap catastrophe in quantum dots

Sarath Sankar·Corentin Bertrand·Antoine Georges·Eran Sela·Yigal Meir
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Abstract

The Anderson overlap catastrophe (AOC) is a many-body effect arising as a result of a shakeup of a Fermi sea due to an abrupt change of a local potential, leading to a power-law dependence of the density of states on energy. Here we demonstrate that a standard quantum-dot detector can be employed as a highly tuneable probe of the AOC, where the power law can be continuously modified by a gate voltage. We show that signatures of the AOC have already appeared in previous experiments, and give explicit predictions allowing to tune and pinpoint their non-perturbative aspects.

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Sarath Sankar, Corentin Bertrand, Antoine Georges, Eran Sela, Yigal Meir. 2024-02-06. Detector-tuned overlap catastrophe in quantum dots. https://doi.org/10.1103/physrevb.110.085133

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