Investigations of the magnetic transport properties of normal metallic films under the non-uniform magnetic field

We have measured the magnetoconductance (MC) defined by Δσ=σ(H)−σ(0) of two-dimensional Bi films subjected to a periodic magnetic field H, which is produced by a superconducting intermediate state of thick Pb film placed in the immediate vicinity of metal films. Non-linear H dependence of MC has been observed at low magnetic fields. This is not expected from a simple magnetic distribution of normal View the MathML source and superconducting (H=0) domain structure in the intermediate state. For specimen of which Pb film has sharp edges, MC shows the step-like structure. This indicates the strong surface flux pinning effect. On the other hand, in the case of broad edge of Pb film, MC shows the oscillation behavior.