Contrasting Pressure Effects in Sr2VFeAsO3 and Sr2ScFePO3

TL;DR

This study investigates how pressure affects superconductivity in two Fe-based materials, revealing that pressure enhances Tc in Sr2VFeAsO3 but suppresses it in Sr2ScFePO3, highlighting contrasting behaviors.

Contribution

It provides the first comparative analysis of pressure effects on these two related Fe-based superconductors, revealing contrasting responses and potential for high Tc in Sr2VFeAsO3.

Findings

Tc of Sr2VFeAsO3 increases from 36.4 K to 46.0 K under 4 GPa

Tc of Sr2ScFePO3 decreases from 16 K to 5 K under 4 GPa

Contrasting pressure effects suggest different underlying mechanisms

Abstract

We report the resistivity measurements under pressure of two Fe-based superconductors with a thick perovskite oxide layer, Sr2VFeAsO3 and Sr2ScFePO3. The superconducting transition temperature Tc of Sr2VFeAsO3 markedly increases with increasing pressure. Its onset value, which was Tc{onset}=36.4 K at ambient pressure, increases to Tc{onset}=46.0 K at ~4 GPa, ensuring the potential of the "21113" system as a high-Tc material. However, the superconductivity of Sr2ScFePO3 is strongly suppressed under pressure. The Tc{onset} of ~16 K decreases to ~5 K at ~4 GPa, and the zero-resistance state is almost lost. We discuss the factor that induces this contrasting pressure effect.