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arXiv · 0809.4732

Bi-collinear antiferromagnetic order in the tetragonal $α$-FeTe

Fengjie Ma·Wei Ji·Jiangping Hu·Zhong-Yi LU·Tao Xiang
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Abstract

By the first-principles electronic structure calculations, we find that the ground state of PbO-type tetragonal $α$-FeTe is in a bi-collinear antiferromagnetic state, in which the Fe local moments ($\sim2.5μ_B$) are ordered ferromagnetically along a diagonal direction and antiferromagnetically along the other diagonal direction on the Fe square lattice. This bi-collinear order results from the interplay among the nearest, next nearest, and next next nearest neighbor superexchange interactions $J_1$, $J_2$, and $J_3$, mediated by Te $5p$-band. In contrast, the ground state of $α$-FeSe is in the collinear antiferromagnetic order, similar as in LaFeAsO and BaFe$_2$As$_2$.

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Fengjie Ma, Wei Ji, Jiangping Hu, Zhong-Yi LU, Tao Xiang. 2008-09-29. Bi-collinear antiferromagnetic order in the tetragonal $α$-FeTe. https://doi.org/10.1103/physrevlett.102.177003

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