Enhanced Radio-Frequency Sensors Based on a Self-Dual Emitter-Absorber

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 10(-2) 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.

Automated summary

A self-dual parity-time-symmetric electronic system was experimentally demonstrated in the radio-frequency region, showing remarkable modulation depth. The system exhibited high sensitivity, detecting even ultrasmall perturbations and showing significantly different responses between emitter and absorber modes. This could lead to the development of monotonic rf sensors with high sensitivity and resolvability.