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arXiv · 1312.1775

First Principles Study of the Magnetic Properties of LaOMnAs

Shuai Dong·Wei Li·Xin Huang·Elbio Dagotto
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Abstract

Recent experiments reported giant magnetoresistance at room temperature in LaOMnAs. Here a density functional theory calculation is performed to investigate magnetic properties of LaOMnAs. The ground state is found to be the G-type antiferromagnetic order within the $ab$ plane but coupled ferromagnetically between planes, in agreement with recent neutron investigations. The electronic band structures suggest an insulating state which is driven by the particular G-type magnetic order, while a metallic state accompanies the ferromagnetic order. This relation between magnetism and conductance may be helpful to qualitatively understand the giant magnetoresistance effects.

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Shuai Dong, Wei Li, Xin Huang, Elbio Dagotto. 2013-12-06. First Principles Study of the Magnetic Properties of LaOMnAs. https://doi.org/10.1063/1.4867757

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