Effect of random distortions on the critical field in layered superconductors

Distortions of the layers in layered superconductors result in a decrease of the critical magnetic field. The distortions have the greatest influence when the field is applied at small angles to the layers. The critical field is calculated in the limits of large and small distortions. When the size of the distortion is less than the coherence length, superconductivity is destroyed by the usual second-order transition. In the opposite limiting case the possibility of superconducting current flow is determined by the percolation properties of the system. The dependence of the resistance on the value and on the angle of the magnetic field with respect to the layers is calculated in the percolation region.