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arXiv · 1003.2039

Electronic Structure Calculations of Magnetic Exchange Interactions in Europium Monochalcogenides

Xiangang Wan·Jinming Dong·Sergej Y. Savrasov
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Abstract

Using a combination of local spin density and Hubbard 1 approximations we study the mechansim of exchange interacion in EuX (X=O, S, Se and Te). We reproduce known experimental results about bulk modulus, critical pressure for structural phase transition, magnetic ordering temperature, spin--wave dispersions as well as momentum-- and tempearuture--dependent band shift. Our numerical results show pressure induced competition between the hybirization enhanced exchange interaction and Kondo--like coupling in EuO. Possible ways to enhance T_{c} are discussed.

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Xiangang Wan, Jinming Dong, Sergej Y. Savrasov. 2010-03-10. Electronic Structure Calculations of Magnetic Exchange Interactions in Europium Monochalcogenides. https://doi.org/10.1103/physrevb.83.205201

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