Pressure Effect on the Superconducting and Magnetic Transitions of the Superconducting Ferromagnet RuSr2GdCu2O8

TL;DR

This study investigates how high pressure affects the superconducting and magnetic transition temperatures in RuSr2GdCu2O8, revealing a small pressure effect on superconductivity and a larger increase in ferromagnetism, suggesting competition between these states.

Contribution

It provides new high-pressure data on RuSr2GdCu2O8, showing differential pressure responses of superconducting and magnetic transitions, indicating their competitive relationship.

Findings

Superconducting transition temperature, Tc, shifts minimally under pressure.

Ferromagnetic transition temperature, Tm, increases significantly with pressure.

Evidence suggests competition between superconducting and ferromagnetic states.

Abstract

The superconducting ferromagnet RuSr2GdCu2O8 was investigated at high pressure. The intra-grain superconducting transition temperature, Tc, is resolved in ac-susceptibility as well as resistivity measurements. It is shown that the pressure shift of Tc is much smaller than that of other high-Tc compounds in a similar doping state. In contrast, the ferromagnetic transition temperature, Tm, increases with pressure at a relative rate that is about twice as large as that of Tc. The high-pressure data indicate a possible competition of the ferromagnetic and superconducting states in RuSr2GdCu2O8.