Dynamical barrier for flux penetration in a superconducting film in the flux flow state

摘要

The penetration of transverse magnetic flux into a thin superconductingsquare film in the flux flow state is considered by numerical simulation. Dueto the film self-field, the governing equations are nonlinear, and incombination with the finite viscosity of the moving vortices, this sets up adynamical barrier for flux penetration into the sample. The correspondingmagnetization loop is hysteric, with the peak in magnetization shifted from thezero position. The magnetic field in increasing applied field is found to forma well-defined front of propagation. Numerical estimates shows that thedynamical barrier should be measurable on films with low volume pinning.