Recent Advances in Iron-based Superconducting Coated Conductors

Abstract

The discovery of high-temperature superconductivity in iron-based superconductors (IBSs) as the second class of high-temperature superconducting transition materials after the cuprates has given a considerable impact on fundamental and applied superconductivity research. Due to their superior superconducting properties, including extremely high upper critical fields, small anisotropy, advantageous grain boundary (GB) feature and relatively high critical transition temperatures, numerous studies have been performed to understand the physical nature and to promote the high-field applications. Consequently, in recent years, a stepwise progress has been made in the synthesis of coated conductors (CCs) based on IBS materials, in order to verify their application potential in a high-field regime. We focus this review on the developments and progress in IBS CCs, in particular on application-oriented properties, such as buffer layer, texture, GBs, and transport properties. Here, we provide an overview of the state-of-the-art in three representative IBS systems (11, 122 and 1111 system) widely studied in CCs, along with a detailed description of the fabrication conditions for each system by molecular beam epitaxy or pulsed laser deposition. A summary and comparison of the relations between the superconducting layers and metal tape templates will be presented. An overview and upcoming research and development outlook for IBS CCs is presented in the conclusion.