Penetration of magnetic field into superconducting mercury.

摘要: IT is well known that a magnetic field almost completely excluded from superconductor, so long cylinder has diamagnetic susceptibility which 1/4 for parallel to the axis, or 1/2 transverse field. The does, however, penetrate slightly, actual should be slightly smaller than X0, and elementary considerations show we have where defines penetration depth r radius. Previous experiments by one of us1 on colloidal mercury, Appleyard others2 thin mercury films (in both cases involving specimen size comparable ), showed order 10-5 cm. increases several times as temperature approaches transition point (4.17° K.). Thus cylinders with radii 10-3 vary few percent close 4.17° K.