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arXiv · 2310.18259

Exploring the impact of fluctuation-induced criticality on non-hermitian skin effect and quantum sensors

Clement Ehrhardt·Jonas Larson
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Abstract

In this paper, we present a concrete example that highlights how predictions in non-Hermitian quantum mechanics can be inaccurately influenced by the absence of environment-induced fluctuations in the model. Specifically, we investigate the non-Hermitian skin effect and sensor in the Hatano-Nelson model, contrasting it with a more precise Lindblad description. Our analysis reveals that these phenomena can undergo breakdown when environmental fluctuations come to the forefront, resulting in a non-equilibrium phase transition from a localized skin phase to a delocalized phase. Beyond this specific case study, we engage in a broader discussion regarding the interpretations and implications of non-Hermitian quantum mechanics. This examination serves to broaden our understanding of these phenomena and their potential consequences.

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Clement Ehrhardt, Jonas Larson. 2023-10-27. Exploring the impact of fluctuation-induced criticality on non-hermitian skin effect and quantum sensors. https://doi.org/10.1103/physrevresearch.6.023135

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