Tuning of competing magnetic and superconducting phase volumes in LaFeAsO$_0.945F_0.055 by hydrostatic pressure

TL;DR

This study investigates how hydrostatic pressure influences the balance between magnetic and superconducting phases in LaFeAsO_0.945F_0.055, revealing pressure-induced phase separation and competition.

Contribution

It provides new insights into pressure-tuned phase competition and spatial separation between magnetism and superconductivity in this material.

Findings

Pressure decreases magnetic ordering temperature T_N

Pressure increases superconducting transition temperature T_c

Magnetic and superconducting regions tend to spatially separate under pressure

Abstract

The interplay between magnetism and superconductivity in LaFeAsO_0.945F_0.055 was studied as a function of hydrostatic pressure up to p~2.4GPa by means of muon-spin rotation (\muSR) and magnetization measurements. The application of pressure leads to a substantial decrease of the magnetic ordering temperature T_N and a reduction of the magnetic phase volume and, at the same time, to a strong increase of the superconducting transition temperature T_c and the diamagnetic susceptibility. From the volume sensitive \muSR measurements it can be concluded that the superconducting and the magnetic areas which coexist in the same sample are inclined towards spatial separation and compete for phase volume as a function of pressure.