Defining regions of normal and anomalous skin effect of sintered Bi-based superconductors by the SRPM method

Abstract

An attempt to develop a method to simultaneously estimate both the resistivity /spl rho/ and the magnetic penetration depth /spl lambda/ by vectorially measuring the difference in the impedance between two circular solenoid coils, one with and the other without a cylindrical superconductor, has been made. It was ascertained that the regions of normal and anomalous skin effect can be defined from the frequency dependence of the difference in the impedance between the two coils. The mean free path of electrons l is evaluated by applying the frequency dependence of the difference in the impedance of the coils to the anomalous skin effect region. The values of /spl rho/, /spl lambda/ and l of Bi-based sintered bulks with different J/sub c/ were evaluated at liquid N/sub 2/ temperature.