Abstract
We propose and experimentally demonstrate a parity-time-symmetric electronic system exhibiting the self-dual emitter-absorber property with a remarkable modulation depth in the radio-frequency (rf) region. The dramatically different rf responses between the emitter and absorber modes may allow detection of ultrasmall conductive or reactive perturbations. Our measurement results show that even a perturbation on the order of can greatly change the system’s output intensity by more than 30 dB, consistent with the theoretical prediction. The measured sensitivity is far beyond the sensitivity of traditional sensors based on a Fabry-Perot resonator, and may lead to monotonic rf sensors with high sensitivity and resolvability.
- Received 10 September 2020
- Revised 18 November 2020
- Accepted 8 December 2020
DOI:https://doi.org/10.1103/PhysRevApplied.15.014026
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