Attenuation analysis of superconducting transmission line using two dimensional Time-Dependent-Ginzburg-Landau equation

Using the two dimensional Time-Dependent-Ginzburg-Landau equation, we analyzed the relationship between the propagation power and the attenuation of a superconducting microstrip line. An analytical solution was derived by the iteration method under the assumptions that the propagation mode was the TEM mode and that the vector potential exponentially decayed in the superconductor. In the case of a Nb-SiO/sub 2/-Nb structure microstrip line at 4.2 K, the power attenuation increased about 30% when the propagation power increased 20 dB at frequencies greater than 400 GHz.