THE SUPERCONDUCTING MIXED-STATE OF ARTIFICIAL MICROSTRUCTURES

The use of ordered microstructures makes it possible, on the one hand, to obtain new (including quantitative) information on elementary pinning forces and on methods of their summation and, on the other hand, to observe interesting effects based on the coherent behaviour of Abrikosov vortices in them. Some progress in these fields of research, has been achieved at the present time. We believe that today the study of quasiperiodic structures and, in particular, pinning in these structures, is also a topical problem. This is because these structures are an intermediate case between fully ordered superconducting lattices and the chaotic system of pinning centres which exists in ordinary superconductors. One of the basic objectives of this review was to demonstrate the existence of interesting problems from the viewpoints of both fundamental and applied physics in this area. It should also be stated that because of the rapid development of technology it is hoped that soon it will be possible to create both more complex and more advanced microstructures, specifically for improving the critical parameters of superconducting materials. This also shows the importance of this field of research.