Fig. 1: Physically unclonable function (PUF) based cryptographic keys generated by the PT-symmetric electronic system.
From: Spectral sensitivity near exceptional points as a resource for hardware encryption
a Illustration of the PUF-enabled secure radio-frequency (RF) authentication and communication. b Generation of the challenge-response pair (CRP) and the cryptographic key in the proposed PUF system; here, \({f}_{0}=\frac{1}{2\pi \sqrt{{{{{LC}}}}}}\) is the natural frequency of the “LC” oscillator and T0 = 1/f0. Our experiments utilize the pulse excitation shown in the left panel of b, and the response, represented by the transient voltage signal measured across the reader’s capacitor, and its discretized form are shown in the middle and right panels of b, respectively. After proper sampling and processing, the analog response is converted to a digital key composed of a bitstring.
