Current and Temperature Controlled Variable Inductance in Superconducting Microstrip Lines

초록

The inductance of superconductiong microstrip lines is measured both as a function of current and temperature. The measurements are performed at 10 MHz for both meander and straight lines by using a multi-frequency LCR meter. The normal state resistance is observed to follow a linear temperature dependence with a slop of 3.59×10-3/K for the straight line and with a slop of 2.96×10-3/K for the meander line. The change in inductance is well described by a quadratic dependence on temperature. This result is consistent with an unconventional pairing state. As for the dependence on the bias current, the inductance shows a squared dependence on the bias current. The results for the current and temperature-controlled inductance are in good agreement with an equation derived using the Ginzburg-Landau theory for the case of thin films.