TY  - JOUR
PB  - SciPost Foundation
DO  - 10.21468/SciPostPhys.16.1.002
TI  - Observation of non-local impedance response in a passive electrical circuit
PY  - 2024/01/04
UR  - https://scipost.org/SciPostPhys.16.1.002
JF  - SciPost Physics
JA  - SciPost Phys.
VL  - 16
IS  - 1
SP  - 002
A1  - Zhang, Xiao
AU  - Zhang, Boxue
AU  - Zhao, Weihong
AU  - Lee, Ching Hua
AB  - In media with only short-ranged couplings and interactions, it is natural to assume that physical responses must be local. Yet, we discover that this is not necessarily true, even in a system as commonplace as an electric circuit array. This work reports the experimental observation of non-local impedance response in a designed circuit network consisting exclusively of passive elements such as resistors, inductors and capacitors (RLC). Measurements reveal that the removal of boundary connections dramatically affects the two-point impedance between certain distant nodes, even in the absence of any amplification mechanism for the voltage signal. This non-local impedance response is distinct from the reciprocal non-Hermitian skin effect, affecting only selected pairs of nodes even as the circuit Laplacian exhibits universally broken spectral bulk-boundary correspondence. Surprisingly, not only are component parasitic resistances unable to erode the non-local response, but they in fact give rise to novel loss-induced topological modes at sufficiently large system sizes, constituting a new manifestation of the critical non-Hermitian skin effect. Our findings chart a new route towards attaining non-local responses in photonic or electrical metamaterials without involving non-linear, non-local, active or amplificative elements.
ER  -

@Article{10.21468/SciPostPhys.16.1.002,
	title={{Observation of non-local impedance response in a passive electrical circuit}},
	author={Xiao Zhang and Boxue Zhang and Weihong Zhao and Ching Hua Lee},
	journal={SciPost Phys.},
	volume={16},
	pages={002},
	year={2024},
	publisher={SciPost},
	doi={10.21468/SciPostPhys.16.1.002},
	url={https://scipost.org/10.21468/SciPostPhys.16.1.002},
}