Observation of higher-order exceptional points in pseudo-Hermitian radio-frequency circuits
Abstract
Exceptional points (EP) in non-Hermitian systems have been widely investigated due to their enhanced sensitivity in comparison to standard systems. In this letter, we report the observation of higher-order pseudo-Hermitian degeneracies in an electronic platform comprised of three inductively coupled gain-loss-loss LC resonators. Theoretical analysis demonstrates that the proposed system can realize third-order EP with asymmetric coupling between adjacent inductors and an arbitrary scaling factor between two loss resonators. When capacitive perturbation is introduced on the middle resonator, the perturbed eigenfrequencies follow a cube-root dependence on the perturbation parameter; in this case, the sensitivity is significantly greater than conventional wireless readout methods. Our work enriches the explorations of higher-order EP on electronic platforms and provides a new degree of design freedom for the non-Hermitian-EP-enhanced wireless sensing system.
Keywords
Cite
@article{arxiv.2305.00900,
title = {Observation of higher-order exceptional points in pseudo-Hermitian radio-frequency circuits},
author = {Ke Yin and Xianglin Hao and Yuangen Huang and Jianlong Zou and Xikui Ma and Tianyu Dong},
journal= {arXiv preprint arXiv:2305.00900},
year = {2023}
}