Title :
Magnetovolume Effects in Heusler Compounds via First-Principles Calculations
Author :
Goncalves, Joao Nuno ; Sequeira Amaral, Joao ; Sequeira Amaral, Vitor
Author_Institution :
Dept. de FisicaCentro de Investig. em Mater. Ceramicos e Compositos, Univ. de Aveiro, Aveiro, Portugal
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 L21-type Co2YZ 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.
Keywords :
Curie temperature; KKR calculations; ab initio calculations; aluminium alloys; cobalt alloys; density functional theory; exchange interactions (electron); magnetocaloric effects; magnetomechanical effects; manganese alloys; silicon alloys; Co2MnAl; Co2MnSi; Heusler alloys; Heusler compounds; Korringa-Kohn-Rostoker method; density functional theory; exchange interaction energies; first-principles calculations; magnetic refrigeration; magnetocaloric effects; magnetovolume effects; mean field Curie temperature; Approximation methods; Compounds; Elementary particle exchange interactions; Lattices; Metals; Saturation magnetization; Temperature; Curie temperature; Heusler; density functional theory; exchange interactions; magnetovolume effect;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2014.2326892
