Effect of pressure on electric transport properties of carbon-doped EuB6

TL;DR

This study investigates how external pressure affects the electrical resistivity of carbon-doped EuB6, revealing that pressure shifts the resistivity maximum to lower temperatures, influenced by inhomogeneous carbon distribution.

Contribution

It demonstrates the impact of pressure on resistivity behavior in inhomogeneous EuB6, highlighting the role of carbon-rich regions in magnetotransport properties.

Findings

Resistivity maximum shifts to lower temperature under pressure.

Inhomogeneous carbon distribution affects ferromagnetic phase percolation.

Pressure influences the volume fraction of non-ferromagnetic regions.

Abstract

We report about influence of external pressure on electrical resistivity of EuB5.99C0.01, the compound believed to be intrinsically inhomogeneous due to fluctuation of carbon content. Our results show that the low-temperature resistivity maximum shifts to lower temperature with applied pressure, opposite to the behavior reported for stoichiometric EuB6. The origin of such qualitative difference we associate with the increasing volume fraction of the phase that is not compatible with ferromagnetic ordering (originating in regions with relatively higher carbon concentratio) with enhancing pressure. Our results support a recent proposition that carbon-rich regions strongly influence magnetotransport properties of carbon-doped EuB6, such as they play a role of spacers, which prevent percolation of ferromagnetic phase.