Enhanced Wireless Readout Near Gain–Loss Detuned Non-Hermitian Exceptional Points

Wireless sensing systems have significant applications in environmental monitoring and medical diagnostics. Although exceptional point (EP) in non-Hermitian parity-time (PT) symmetric system can significantly enhance perturbation sensitivity, making them highly promising for ultrasensitive wireless sensing, their practical implementation is hindered by the stringent requirement for precise gain-loss matching between the reader and the sensor. Furthermore, the resolution of such systems deteriorates markedly under asymmetric perturbations. Here, we develop a PT-symmetric wireless sensing system with gain–loss detuning that maintains high-resolution frequency shifts despite slight gain-loss mismatches between components. Through theoretical analysis, we demonstrate that this system achieves sensitivity comparable to that of PT-symmetric systems while overcoming their inherent limitations. Experimental validation through pressure sensing demonstrates that the detuned PT-symmetric system achieves high-resolution detection under tiny capacitive pressure perturbations while attaining a sensitivity of 1.85 MHz/N. Our work indicates potential implications for practical applications of ultra-sensitive sensors.