Spectral properties of stochastic resonance in quantum transport

TL;DR

This paper explores the spectral characteristics of stochastic resonance in quantum dots, revealing a bifurcation in noise spectra linked to quantized pumping, through both theoretical models and experimental data.

Contribution

It introduces a generalized renewal theory approach and a master equation method for analyzing noise spectra in driven quantum transport systems.

Findings

Identification of a bifurcation in the noise spectrum near the stochastic resonance point

Development of a generalized method for spectral analysis from waiting times

Experimental validation of spectral transition in quantum dot systems

Abstract

We investigate theoretically and experimentally stochastic resonance in a quantum dot coupled to electron source and drain via time-dependent tunnel barriers. A central finding is a transition visible in the current noise spectrum as a bifurcation of a dip originally at zero frequency. The transition occurs close to the stochastic resonance working point and relates to quantized pumping. For the evaluation of power spectra from measured waiting times, we generalize a result from renewal theory to the ac driven case. Moreover, we develop a master equation method to obtain phase-averaged current noise spectra for driven quantum transport.