The surface impedance of superconductors and normal metals at high frequencies III. The relation between impedance and superconducting penetration depth

摘要: The theory developed in II is extended to cover the case of a superconductor, and formula derived relating r.f. resistivity superconducting penetration depth other parameters metal. It shown how may be deduced directly from measurements skin reactance, method measuring reactance described, based essentially on variation velocity propagation along transmission line due conductors. For technical reasons it not convenient measure absolutely, but simple extension technique described I enables change accurately measured when superconductivity destroyed by magnetic field. has been applied mercury tin. In former results are agreement with Shoenberg's direct measurements, confirm that at 0 degrees K order 7 $\times $ 10$^{-6}$ cm. beginning paper used deduce temperature I, determinations fairly good, perfect. Some assumptions developing critically discussed, qualitative account given show Heisenberg's offers an explanation some salient features particular indicates relation between normal electrons.