Effect of thermal history on magnetism in UCoGa

TL;DR

This study investigates how different thermal treatments affect the magnetic properties of UCoGa crystals, linking defect concentration to coercivity and Curie temperature, and confirming domain-wall pinning as a key mechanism.

Contribution

It provides new insights into the relationship between thermal history, defect levels, and magnetic behavior in UCoGa, highlighting domain-wall pinning effects.

Findings

Higher residual resistivity correlates with increased coercive field.

Thermal treatments influence magnetic parameters via defect concentration.

Domain-wall pinning explains coercivity variations in UCoGa.

Abstract

Single crystals of UCoGa have been grown in different conditions and subsequently annealed in order to provide a collection of samples representing various quality as to concentration of lattice defects. The different sample quality "grades" have been characterized by values of residual electrical resistivity. Correlations of magnetic parameters (coercive field, Curie temperature) with residual resistivity have been determined and domain-wall pinning by crystal defects has been confirmed as the underlying mechanism of coercive field in strongly anisotropic ferromagnets.