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arXiv · 0908.3044

Nonzero macroscopic magnetization in half-metallic antiferromagnets at finite temperatures

Ersoy Sasioglu
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Abstract

Combining density-functional theory calculations with many-body Green's-function technique, we reveal that the macroscopic magnetization in half-metallic antiferromagnets does not vanish at finite temperature as for the T=0 limit. This anomalous behavior stems from the inequivalent magnetic sublattices which lead to different intrasublattice exchange interactions. As a consequence, the spin fluctuations suppress the magnetic order of the sublattices in a different way leading to a ferrimagnetic state at finite temperatures. Computational results are presented for the half-metallic antiferromagnetic CrMnZ (Z=P,As,Sb) semi-Heusler compounds.

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Ersoy Sasioglu. 2009-08-21. Nonzero macroscopic magnetization in half-metallic antiferromagnets at finite temperatures. https://doi.org/10.1103/physrevb.79.100406

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