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Band-theoretical prediction of magnetic anisotropy in uranium monochalcogenides

Tatsuya Shishidou·Tamio Oguchi
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Abstract

Magnetic anisotropy of uranium monochalcogenides, US, USe and UTe, is studied by means of fully-relativistic spin-polarized band structure calculations within the local spin-density approximation. It is found that the size of the magnetic anisotropy is fairly large (about 10 meV/unit formula), which is comparable with experiment. This strong anisotropy is discussed in view of a pseudo-gap formation, of which crucial ingredients are the exchange splitting of U 5f states and their hybridization with chalcogen p states (f-p hybridization). An anomalous trend in the anisotropy is found in the series (US>>USe<UTe) and interpreted in terms of competition between localization of the U 5f states and the f-p hybridization. It is the spin-orbit interaction on the chalcogen p states that plays an essential role in enlarging the strength of the f-p hybridization in UTe, leading to an anomalous systematic trend in the magnetic anisotropy.

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Tatsuya Shishidou, Tamio Oguchi. 2000-02-03. Band-theoretical prediction of magnetic anisotropy in uranium monochalcogenides. https://doi.org/10.1103/physrevb.62.11747

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