Tuning the magnetocrystalline anisotropy in $R$CoPO by means of $R$ substitution: a ferromagnetic resonance study

TL;DR

This study uses broad-band electron spin resonance to show how substituting different rare-earth elements in $R$CoPO tunes the magnetocrystalline anisotropy, revealing the interplay of structural and electronic effects.

Contribution

It demonstrates that rare-earth substitution effectively modifies the magnetocrystalline anisotropy in $R$CoPO, highlighting the role of structural and $f$-$d$ orbital interactions.

Findings

Rare-earth substitution induces easy-plane anisotropy.

Structural effects influence magnetic properties.

$f$-$d$ orbital interactions are key to anisotropy tuning.

Abstract

We report on broad-band electron spin resonance measurements performed within the itinerant ferromagnetic phase of $R$CoPO ($R$ = La, Pr, Nd and Sm). We reveal that the $R$ substitution is highly effective in gradually introducing a sizeable easy-plane magnetocrystalline anisotropy within the Co sublattice. We explain our results in terms of a subtle interplay of structural effects and of indirect interactions between the $f$ and $d$ orbitals from $R$ and Co, respectively.