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arXiv · 2512.11679

Arbitrary-order exceptional points in a nanomechanical cavity

Ning Wu·Kaiyu Cui·Ziming Chen·Chenxuan Wang·Xue Feng·Fang Liu·Wei Zhang·Hao Sun·Yongzhuo Li·Yidong Huang
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Abstract

Higher-order exceptional points (EPs) govern non-Hermitian system dynamics through their enriched and sharpened spectral topology, yet the intrinsic topological fragility hinders robust experimental realization. Here, we present a scalable architecture that implements arbitrary-order EPs via a recurrent network comprising a single nanomechanical resonator and unlimited virtual resonators. We experimentally realize mechanical EPs up to the seventh order and confirm this architecture's scalability. Moreover, we reveal that the fundamental noise component and the measured signal share the same system coupling channel and thus undergo identical root-response amplification near EPs of arbitrary order, consistent with our signal-to-noise ratio measurements. Our work establishes a general platform for exploring higher-order EP-based phenomena while clarifying the fundamental boundary of non-Hermitian sensitivity enhancement across diverse physical systems.

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Ning Wu, Kaiyu Cui, Ziming Chen, Chenxuan Wang, Xue Feng, Fang Liu, Wei Zhang, Hao Sun, Yongzhuo Li, Yidong Huang. 2025-12-12. Arbitrary-order exceptional points in a nanomechanical cavity. https://arxiv.org/abs/2512.11679

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