A nonlinear transmission line model for superconducting stripline resonators

Abstract

A nonlinear transmission line model is used to explain the nonlinear frequency response at high input power levels of stripline resonators fabricated with superconducting NbN and YBa/sub 2/Cu/sub 3/O/sub 7-x/ thin films. The resonator is modeled as a transmission line with a nonlinear inductance and resistance. The inductor flux and resistor voltage drop are assumed to be odd polynomial functions of the transmission line current, and the polynomial coefficients are adjusted to match the measured data. Excellent agreement is found between the measured and calculated results.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>