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arXiv · 2202.07972

Two-way enhancement of sensitivity by tailoring higher-order exceptional points

Ambaresh Sahoo·Amarendra K. Sarma
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Abstract

Higher-order exceptional points in non-Hermitian systems have recently been used as a tool to engineer high-sensitivity devices, attracting tremendous attention from multidisciplinary fields. Here, we present a simple yet effective scheme to enhance the device sensitivity by slightly deviating the gain-neutral-loss linear configuration to a triangular one, resulting in an abrupt phase transition from third-order to second-order exceptional points. Our analysis demonstrates that the exceptional points can be tailored by a judicious tuning of the coupling parameters of the system, resulting in enhanced sensitivity to a small perturbation. The tunable coupling also leads to a sharp change in the sensitivity slope, enabling the perturbation to be measured precisely as a function of coupling. This two-way detection of the perturbation opens up a rich landscape toward ultra-sensitive measurements, which could be applicable to a wide range of non-Hermitian ternary platforms.

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Ambaresh Sahoo, Amarendra K. Sarma. 2022-02-16. Two-way enhancement of sensitivity by tailoring higher-order exceptional points. https://doi.org/10.1103/physreva.106.023508

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