Microwave, Flux Flow, and Fluctuation Resistance of Dirty Type-II Superconductors

Abstract

We have reexamined the recent theories by Caroli and Maki of the dynamic response of dirty superconductors and find them inconsistent and incomplete. Additional contributions, which were not included by them, are calculated, and new expressions are presented for the microwave and flux-flow resistance. In particular, we find that the use of the time-dependent Ginzburg-Landau equation for the order parameter, coupled with the static Ginzburg-Landau equation for the current, is not generally adequate to calculate the leading superconducting contributions to the resistance. These results imply that the theory of Aslamazov and Larkin for the extra conductivity due to fluctuations above the transition temperature is also incomplete and that, in general, additional contributions of the type suggested by Maki must be included.