Resistivity saturation in PrFeAsO$_{1-x}$F$_y$ superconductor: An evidence of strong electron-phonon coupling

TL;DR

This study investigates resistivity behavior in PrFeAsO$_{1-x}$F$_y$ superconductors, revealing strong electron-phonon coupling and supporting phonon-mediated BCS superconductivity in Fe-based oxypnictides.

Contribution

It provides experimental evidence of strong electron-phonon interaction and estimates normal-state parameters, advancing understanding of superconductivity mechanisms in this material.

Findings

Resistivity shows linear temperature dependence above 170 K.

Resistivity saturation at higher temperatures indicates strong electron-phonon coupling.

Results support phonon-mediated BCS superconductivity in PrFeAsO$_{1-x}$F$_y$.

Abstract

We have measured the resistivity of PrFeAsO$_{1-x}$F$_y$ samples over a wide range of temperature in order to elucidate the role of electron-phonon interaction on normal- and superconducting-state properties. The linear T dependence of $\rho$ above 170 K followed by a saturationlike behavior at higher temperature is a clear signature of strong electron-phonon coupling. From the analysis of T dependence of $\rho$, we have estimated several normal-state parameters useful for understanding the origin of superconductivity in this system. Our results suggest that Fe-based oxypnictides are phonon mediated BCS superconductors like Chevrel phases and A15 compounds.