SURFACE-BARRIER IN THE MIXED-STATE OF TYPE-II SUPERCONDUCTORS NEAR-EQUILIBRIUM

We have calculated the energy barrier for penetration of straight vortices through a plane surface into a type-II superconductor which contains an equilibrium vortex lattice. The most favorable penetration channel ends with the creation of a surface interstitial. The height of the barrier is strongly affected by the lattice deformations caused by the penetrating vortex. The proposed mechanism governs the penetration and exit of vortices through the edges of thin superconducting films. The results are in good agreement with experimental values of the barrier obtained by White et al. (Phys. Rev. Lett. 70 (1993) 670) from the edge resistivity of narrow strips of a-MoGe films.