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arXiv · 1612.09133

Magnetovolume Effects in Heusler Compounds via First-Principles Calculations

J. N. Gonçalves·J. S. Amaral·V. S. Amaral
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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.

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J. N. Gonçalves, J. S. Amaral, V. S. Amaral. 2016-12-29. Magnetovolume Effects in Heusler Compounds via First-Principles Calculations. https://doi.org/10.1109/tmag.2014.2326892

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