Analysis of pulse propagation on high-Tc superconducting transmission lines

The propagation characteristics of high-T_c superconducting microstrip transmission lines are calculated from the viewpoint of interconnection technology. A detailed analysis was made to examine the attenuation and phase velocity of a pulse on a YBCO transmission line, taking into consideration of dielectric loss of the MgO substrate. The results of this analysis are compared with the measured propagation constants of YBCO strip line fabricated on a MgO substrate. It is shown that the effect of dielectric loss of a substrate to the attenuation of a microstrip line is dominant and cannot be neglected as long as a MgO substrate is used. How a pulse propagates on the superconducting transmission line and how the circuit parameters of transmission line affect the propagation characteristics of the line were investigated. Simulation results show that the high-T_c superconducting transmission lines are more promising for interconnections than the conventional transmission lines by virtue of their lower attenuation and less dispersion, even if a dielectric loss of a MgO substrate is taken into consideration