Speaker
Description
Artificial pinning centers (APCs) of varying types and nano-scale size have been successfully introduced into (Y,RE)Ba2Cu3O7-x ((Y,RE)BCO or Y-RE-Ba-Cu-O) thin film superconductors by different processing methods, in order to strongly pin the quantized vortices. As a result, the critical current densities (Jcs) of these high-temperature-superconductor (HTS) films have been dramatically improved, for a wide landscape of temperature from 4.2K to 85K, applied magnetic fields B = 0T to 33T, and B-field orientation θ = 0 to 90°. A number of high quality reviews of this large field have been published, that describe progress in the fundamental sciences and pseudo-empirical approaches to improving Jc(B,T,θ) properties. This review focuses on two different subtopics: i) plotting historical progress world-wide since 1995 in improving Jc(B,T) and whole-wire engineering current density Je(B,T) properties, by data-mining the 80+ highest cited papers in the field, and ii) showing how improvements of Je(B,T) can have significant impact to improve the performance and capabilities of high power devices and applications. From this review, it easier to identify the best APC flux pinning systems, and understand the relative lack of published studies for the full Jc(B,T,θ) landscape, and especially for T < 50K and -30° ≤ θ ≤ 120° for select (B,T) values. It is shown that improving flux pinning at all operation temperatures of 4K to 77K contributes to enabling devices to operate at dramatically increasing higher temperatures, which can significantly reduce system cost-size-weight-and-power (C-SWaP). The reduction of C-SWaP is not only beneficial, but can sometimes be critical to enable operation or completely new capabilities, and open up new technologies and markets.
Acknowledgements: Support from the Air Force Office of Scientific Research (AFOSR) and LRIR #18RQCOR100, and the Aerospace Systems Directorate (AFRL/RQ)
