Modeling of the critical state of layered superconducting structures with inhomogeneous layers

In this paper, an approach to calculating the critical state of layered structures consisting of inhomogeneous superconducting layers is proposed. The method is based on the numerical solution of one-dimensional Ginzburg–Landau equations generalized for an inhomogeneous plate. The method makes it possible to obtain dependences of the critical current on the magnetic field, as well as the current and magnetic field distribution over the layers. The averaged critical current of the layered structures consisting of inhomogeneous layers is compared with the averaged critical current of the layered structures consisting of homogeneous layers. It is found that with a small number of layers and relatively low external magnetic field, the critical current of layered structures consisting of homogeneous layers may exceed that of structures consisting of inhomogeneous layers. On the contrary, with the increase in the number of layers and/or external magnetic field strength, the critical current of layered structures consisting of inhomogeneous layers exceeds the critical current of structures consisting of homogeneous layers. The pinning force in the structures consisting of inhomogeneous layers is higher than in the structures consisting of homogeneous layers.