Superconductor relaxation -- A must to be integrated into stability calculations

TL;DR

This paper analyzes superconductor stability and quench phenomena using a dynamic relaxation model and an electrical resistance network, offering new insights into critical temperature measurement and resistivity curve behavior.

Contribution

It re-examines the dynamic relaxation model for high-temperature superconductors and introduces a resistance network approach to better estimate critical temperature and explain resistivity curve bending.

Findings

The relaxation model applies to YBaCuO and BSCCO superconductors.

The resistance network model offers an alternative method for critical temperature estimation.

Results suggest new explanations for resistivity curve bending near critical temperature.

Abstract

A superconductor is stable if it does not quench. Quench is a short-time physics problem. For its deeper understanding of, and how to avoid quench, the physics behind stability has to be analysed. A previously suggested dynamic relaxation model is re-considered and applied to YBaCuO 123 and BSCCO 2223 high-temperature, thin film superconductors. Parallel to this investigation, an unconventional approach using an electrical resistance network (a cell model) is applied to introduce a method how to estimate the extent by which, in resistance measurements, exact determination of critical temperature of superconductors is possible. This resistive cell model, when considering its numerical convergence behaviour, in a side result may provide an alternative explanation of (at least a contribution to) bending of resistivity vs. temperature curves, and perhaps also an alternative to standard explanations of the thermal fluctuations impact on these curves. The dynamic relaxation and the resistance models provide a parenthesis that correlates, in terms of the Ginzburg-Landau order parameter, (i) solution of superconductor stability problem (the main objective of this paper), with tentative explanation of (ii) bending of the resistivity curves near critical temperature and (iii) with predictions from thermal fluctuations.