Magnetovolume Effects in Heusler Compounds via First-Principles Calculations

TL;DR

This study uses first-principles calculations to analyze how hydrostatic pressure influences the magnetic and volume properties of Co2YZ Heusler alloys, aiming to enhance magnetovolume effects for applications like magnetic refrigeration.

Contribution

It provides a detailed first-principles analysis of pressure-dependent magnetic interactions in Co2YZ Heusler alloys, revealing diverse behaviors among different compounds.

Findings

Different pressure derivatives of Curie temperature observed

Qualitative trends vary among studied alloys

Results compared with previous experiments and calculations

Abstract

Heusler alloys are promising for several applications, including magnetic refrigeration, due to high magnetocaloric and magnetovolume effects. One way to optimize this potential is by increasing the magnetovolume effect. Using density functional theory with the Korringa-Kohn-Rostoker method, we calculate the effective exchange interaction energies and corresponding mean field Curie temperature as a function of the volume (hydrostatic pressure) in several L2 1 -type Co 2 YZ Heusler alloys. Different qualitative trends and signs of the pressure derivatives of the Curie temperature and moments are found among these compounds, discussed and compared with previous calculations and experiments.