Critical Behavior of Layered Superconducting Films in Parallel Magnetic Field

摘要

The equilibrium magnetization for layered superconducting films thatexperience a nonzero component, $H_{\parallel}$, of magnetic field appliedparallel to the layers is computed at temperatures and at perpendicular fieldcomponents in the vicinity of the decoupling transition. A fermion analogy isexploited for this purpose, whereby it is found that the parallel magnetizationshows an anomalous $H_{\parallel}^{-1}$ tail at high fields due to entropicfluctuations of the (parallel) lattice of Josephson vortices. A collectivepinning effect is also identified for $c$-axis transport limited by a singleplanar defect oriented parallel to both $c$ and to the applied magnetic field.