Linear dynamics subject to thermal fluctuations and non-Gaussian noise: from classical to quantum

Abstract

The dynamics of a linear system embedded in a heat bath environment and subject to white non-Gaussian noise is studied. Classical higher-order cumulants in coordinate space are derived for Poissonian noise and their impact on the dynamics and on asymptotic steady-state distributions is analyzed. In the quantum regime, non-Gaussian properties are present in reduced density in coordinate representation, but in energy representation they exist on a transient time scale only, due to symmetry. Within an exactly solvable model, our results provide insight into mechanisms of linear detectors as sensors for non-Gaussian noise at high and low temperatures.

Noise-induced effects in nonlinear relaxation of condensed matter systems

“…In fact, great attention has been paid to JJs as superconducting quantum bits [1][2][3][4], nanoscale superconducting quantum interference devices for detecting weak flux changes [5,6], and threshold noise detectors [7][8][9][10]. Moreover JJs are typical out of equilibrium systems characterised by tilted or switching periodic potentials [11,12], and the effects both of thermal and nonthermal noise sources on the transient dynamics of JJs have recently attracted considerable interest [13][14][15][16][17][18][19][20][21][22][23]. In the last decade, theoretical progress has allowed to calculate the entire probability distribution of the noise signal and its cumulants, performing a full counting statistics of the current fluctuations [14].…”

Switching times in long-overlap Josephson junctions subject to thermal fluctuations and non-Gaussian noise sources

“…Specifically, the statistical analysis of the switching from the metastable superconducting state to the resistive running state of the JJ has been proposed to detect weak periodic signals embedded in a noise environment [9,10]. Moreover, the rate of escape from one of the metastable wells of the tilted washboard potential of a JJ encodes information about the non-Gaussian noise present in the input signal [7,8,[24][25][26].…”

Phase dynamics in graphene-based Josephson junctions in the presence of thermal and correlated fluctuations

“…The rate of switching from the JJ metastable superconducting state encodes information about the noise present in an input signal [38][39][40][41][42] . The characterization of JJs as detectors, based on the statistics of the escape times, has been recently proposed [38][39][40][41][42][43][44] . Specifically, the statical analysis of the switching from the metastable superconducting state to the resistive running state of the JJ has been proposed to detect weak periodic signals embedded in a noisy environment 43,44 .…”