Microscale and nanoscale pinning centres in single-domain REBCO superconductors

Abstract

Despite the fact that high-temperature superconductors have been known for more than 30 years, these materials are still intensively studied due to their unique transport and magnetic properties. High-temperature superconducting mixed oxides (YBCO, REBCO, BSSCO, etc.) belong to a group of advanced ceramic materials with a layered structure, heading now towards their applications in various fields of engineering, energetics or industry. The improvement of their properties, mainly the critical current density in a high magnetic field, and thus a high trapped magnetic field, is therefore highly desirable. One of the possible routes for such improvement is implementation of artificial pinning centres in the superconducting single-domain matrix. In this review, we describe the use of various pinning centres and possible methods of their application. In addition, their advantages and disadvantages are summarized and discussed. The main focus is on nanosized pinning centres composed of chemically inert materials and on the bulk type of YBCO/REBCO superconductors used mainly for various superconducting magnetic levitation applications.