Theory of defect-induced crystal field perturbations in rare-earth magnets

A critical problem in the theory and modelling of magnetic materials is quantifying the effect of defects of macroscopic properties with current state-of-the-art models either ignoring defects or treating them heuristically.

The paper 'Theory of defect-induced crystal field perturbations in rare-earth magnets' (published as an Editor's Suggestion in Physical Review Letters) offers an essential step towards solving this problem by deriving an accurate yet inexpensive theoretical model of defects, parameterised by first-principles calculations.

The methodology opens a new avenue in magnetics research by enabling the study of magnetic phenomena, such as domain wall and skyrmion dynamics, under conditions which matched the materials found in nature or synthesised in the laboratory.

The work, involving collaborations with the University of Warwick and Northeastern University, was led by Dr Christopher Patrick and includes calculations carried out by Yixuan Huang as part of a summer research internship in the department.