Theoretical study of the hyperfine field at Cu impurities diluted in an iron host

TL;DR

This paper provides a theoretical analysis of the magnetic hyperfine field at Cu impurities in an iron host, extending existing models to match recent experimental measurements across different Cu isotopes.

Contribution

It introduces an extended Daniel-Friedel model including next neighbor perturbation and Cu anomaly volume effects to explain hyperfine field measurements.

Findings

Model successfully explains experimental hyperfine fields for Cu isotopes in Fe.

Inclusion of Cu anomaly volume improves agreement with data.

Extended model captures impurity effects more accurately.

Abstract

Magnetic hyperfine field at Cu isotopes as impurities in Fe were recently measured at low temperature. A model to explain these experimental results is proposed. The diluted Cu impurities in the ferromagnetic Fe host are described by an extension of the Daniel-Friedel model, including the next neighbor perturbation. In order to account for the available experimental data in Cu isotopes with atomic masses $A$ = 59, 67, 69 and 71 as impurity, we needed to incorporate the Cu anomaly volume in the effective charge to be screened and in the self-consistent procedures.