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arXiv · 2608.20847

Non-Hermitian sensing via end-to-end Green's functions

Hui-Qiang Liang·Yu-Shi Cheng·Guo-Fu Xu
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Abstract

Sensing hinges on two key attributes: high sensitivity and resilience to noise. Here, we present a scheme that unites these features within a single framework. By harnessing the exponential amplification of end-to-end Green's functions-a direct signature of the non-Hermitian skin effect-our scheme achieves an exponential sensitivity scaling of exp({\alpha}L) with {\alpha} a model-specific constant and L the system size. Notably, this enhanced sensitivity is protected by spectral winding numbers and endures under disorder when the non-Hermitian topological phase remains intact. We also explore its feasibility in synthetic non-Hermitian platforms, providing a pathway toward highly sensitive and noise-tolerant sensing.

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Hui-Qiang Liang, Yu-Shi Cheng, Guo-Fu Xu. 2026-08-21. Non-Hermitian sensing via end-to-end Green's functions. https://arxiv.org/abs/2608.20847

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