Parametric Amplification of Nonlinear Response of Single Crystal Niobium

TL;DR

This paper reports a significant enhancement of the nonlinear magnetic response in single crystal niobium through parametric amplification, supported by experimental results and theoretical modeling predicting bifurcations.

Contribution

It demonstrates a novel parametric amplification technique for nonlinear magnetic responses in superconducting niobium, combining experimental observation with theoretical analysis.

Findings

Output signal amplified by about three orders of magnitude

Experimental validation of parametric amplification effect

Theoretical prediction of bifurcations in response behavior

Abstract

Giant enhancement of the nonlinear response of a single crystal Nb sample, placed in {\it a pumping ac magnetic field}, has been observed experimentally. The experimentally observed amplitude of the output signal is about three orders of magnitude higher than that seen without parametric pumping. The theoretical analysis based on the extended double well potential model provides a qualitative explanation of the experimental results as well as new predictions of two bifurcations for specific values of the pumping signal.