Resistive transition of hydrogen-rich superconductors

TL;DR

This paper analyzes the superconducting transition width in hydrogen-rich superconductors and finds that, unlike some recent claims, their transition width broadening under magnetic fields follows conventional trends.

Contribution

It provides a detailed mathematical analysis of magnetoresistive data, demonstrating that hydrogen-rich superconductors exhibit conventional transition width broadening behavior.

Findings

Transition width broadening in hydrogen-rich superconductors follows conventional trends.

Mathematical analysis clarifies the behavior of transition width under magnetic fields.

Contrasts recent claims of unconventional behavior in near-room-temperature superconductors.

Abstract

Critical temperature, $T_c$, and the transition width, $\Delta$$T_c$, are two primary parameters of the superconducting transition. The latter parameter reflects the superconducting state disturbance originating from the thermodynamic fluctuations, atomic disorder, applied magnetic field, the presence of secondary crystalline phases, applied pressure, etc. Recently, Hirsch and Marsiglio (2020 arXiv:2012.12796) performed an analysis of the transition width in several near-room-temperature superconductors (NRTS) and reported that the reduced transition width, $\Delta$$T_c$$/$$T_c$, in these materials does not follow a conventional trend of transition width broadening on applied magnetic field observed in low- and high-$T_c$ superconductors. Here we present thorough mathematical analysis of the magnetoresistive data, $\it{R(T,B)}$, for the high-entropy alloy $(ScZrNb)_{0.65}$$[RhPd]_{0.35}$ and hydrogen-rich superconductors of Im-3m-$H_{3}S$, C2/m-$LaH_{10}$ and P63/mmc-$CeH_9$. We found that the reduced transition width, $\Delta$$T_c$$/$$T_c$, in these materials does follow a conventional broadening trend on applied magnetic field.