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.

中文翻译：

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基于双发射极吸收器的增强型射频传感器

我们提出并通过实验证明了一种奇偶时间对称电子系统，该系统表现出自双发射极吸收体的特性，在射频（rf）区域具有显着的调制深度。发射器和吸收器模式之间的rf响应截然不同，可以检测出超小的导电或电抗扰动。我们的测量结果表明，即使是${10}^{-2}$可以使系统的输出强度大大改变30 dB以上，与理论预测一致。测得的灵敏度远远超出了基于Fabry-Perot谐振器的传统传感器的灵敏度，并且可能导致具有高灵敏度和可分辨性的单调射频传感器。