Experimental observation of induced stochastic transitions in multi-well potential of RF SQUID loop

TL;DR

This paper reports the experimental observation of stochastic resonance in a multi-well RF SQUID loop, demonstrating noise-induced transitions and signal amplification due to binary and Gaussian noise.

Contribution

It provides the first experimental evidence of stochastic resonance involving multiple metastable states in a multi-well RF SQUID, including binary noise effects.

Findings

Amplification of weak signals via stochastic resonance in RF SQUIDs.

Observation of noise-induced transitions between multiple metastable states.

Binary noise influences transitions, enabling noise spectroscopy of the SQUID states.

Abstract

An amplification of a weak low-frequency harmonic signal is experimentally observed in a single-junction-superconducting quantum interferometer (RF SQUID loop) due to stochastic transitions between two or more metastable states of the loop under the applied noise flux of varying intensity (the effect of stochastic resonance, SR). In addition to the usual scenario of the SR in a bistable system with Gaussian noise, the transitions between multiple metastable states of the multi-well SQUID loop potential under the influence of a binary noise is observed. This can be interpreted as a kind of noise "spectroscopy" of the metastable states of the SQUID loop with different values of the trapped magnetic flux.