Variance and Skewness of Current Fluctuations Experimentally Evidenced in Single-Photon Avalanche Diodes

Consistently with recently published theoretical work, we experimentally demonstrate that, in electronic devices exhibiting strongly nonlinear current-voltage characteristics, the white noise cannot be purely Gaussian, as predicted by the stochastic thermodynamic relations. Micro-fabricated silicon single-photon avalanche diodes exemplify this result. Relying on high-accuracy time-domain noise measurements, we go beyond the conventional characterization of fluctuations in terms of mean and variance only by also assessing the third moment (skewness).