Signal Amplification in NbN Superconducting Resonators via Stochastic Resonance

TL;DR

This paper demonstrates how nonlinearity in NbN superconducting resonators, caused by thermal instability, can be exploited to amplify weak microwave signals through stochastic resonance, with analysis of modulation effects.

Contribution

It introduces a novel application of stochastic resonance in NbN superconducting resonators driven by thermal nonlinearity, providing experimental validation and theoretical comparison.

Findings

Small AM microwave signals are amplified via injected white noise.

Amplification depends on modulation amplitude and frequency.

Experimental results align with theoretical predictions.

Abstract

We exploit nonlinearity in NbN superconducting stripline resonators, which is originated by local thermal instability, for studying stochastic resonance. As the resonators are driven into instability, small amplitude modulated (AM) microwave signals are amplified with the aid of injected white noise. The dependence of the signal amplification on the modulation amplitude and the modulation frequency is examined and compared with theory.