Pressure effects on the transport coefficients of Ba(Fe1-xCox)2As2

TL;DR

This study investigates how hydrostatic pressure influences the electrical transport properties and carrier dynamics in BaFe2As2 and its Co-doped variant, revealing pressure-induced modifications in band contributions and carrier concentrations.

Contribution

It provides new insights into pressure effects on transport coefficients and carrier behavior in iron-based superconductors using experimental measurements and modeling.

Findings

Pressure suppresses hole-like thermopower contributions.

Pressure enhances electron contributions to transport.

Two-band model estimates show pressure alters carrier concentrations.

Abstract

We report the temperature dependence of the resistivity and thermoelectric power under hydrostatic pressure of the itinerant antiferromagnet BaFe2As2 and the electron-doped superconductor Ba(Fe0.9Co0.1)2As2. We observe a hole-like contribution to the thermopower below the structural-magnetic transition in the parent compound that is suppressed in magnitude and temperature with pressure. Pressure increases the contribution of electrons to transport in both the doped and undoped compound. In the 10% Co-doped sample, we used a two-band model for thermopower to estimate the carrier concentrations and determine the effect of pressure on the band structure.