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arXiv · 1912.13274

Ferromagnetic kinetic exchange interaction in magnetic insulators

Zhishuo Huang·Dan Liu·Akseli Mansikkamäki·Veacheslav Vieru·Naoya Iwahara·Liviu F. Chibotaru
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Abstract

The superexchange theory predicts dominant antiferromagnetic kinetic interaction when the orbitals accommodating magnetic electrons are covalently bonded through diamagnetic bridging atoms/groups. Here we show that explicit consideration of magnetic and (leading) bridging orbitals, together with the electron transfer between the former, reveals a strong ferromagnetic kinetic exchange contribution. First principle calculations show that it is comparable in strength with antiferromagnetic superexchange in a number of magnetic materials with diamagnetic metal bridges. In particular, it is responsible for a very large ferromagnetic coupling ($-10$ meV) between the iron ions in a Fe$^{3+}$-Co$^{3+}$-Fe$^{3+}$ complex.

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Zhishuo Huang, Dan Liu, Akseli Mansikkamäki, Veacheslav Vieru, Naoya Iwahara, Liviu F. Chibotaru. 2019-12-31. Ferromagnetic kinetic exchange interaction in magnetic insulators. https://doi.org/10.1103/physrevresearch.2.033430

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