Nonlinearities and Parametric Amplification in Superconducting Coplanar Waveguide Resonators

TL;DR

This paper investigates the nonlinear behavior of superconducting niobium coplanar waveguide resonators, demonstrating bifurcation and significant parametric amplification driven by current-dependent kinetic inductance.

Contribution

It provides experimental evidence of nonlinear effects and parametric amplification in superconducting waveguide resonators, highlighting the role of kinetic inductance.

Findings

Bifurcation of the nonlinear oscillator observed.

Parametric amplification with +22.4 dB gain achieved.

Nonlinear properties driven by current-dependent kinetic inductance.

Abstract

Experimental investigations of the nonlinear properties of superconducting niobium coplanar waveguide resonators are reported. The nonlinearity due to a current dependent kinetic inductance of the center conductor is strong enough to realize bifurcation of the nonlinear oscillator. When driven with two frequencies near the threshold for bifurcation, parametric amplification with a gain of +22.4 dB is observed.