Effective quantum pseudospin-1/2 model for Yb pyrochlore oxides

Shigeki Onoda

doi:10.1088/1742-6596/320/1/012065

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arXiv · 1101.1230

Effective quantum pseudospin-1/2 model for Yb pyrochlore oxides

Shigeki Onoda

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Abstract

An effective quantum pseudospin-1/2 Hamiltonian for Yb_2TM_2O_7 (TM = Ti and Sn) is obtained in terms of the atomic Kramers ground doublet of the LS coupling and the crystalline electric field, which is almost described with J^z=\pm 1/2. It is calculated microscopically as the sum of Anderson's superexchange interaction and the magnetic dipole interaction. It is found that it shows a strong exchange anisotropy.

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Shigeki Onoda. 2011-01-06. Effective quantum pseudospin-1/2 model for Yb pyrochlore oxides. https://doi.org/10.1088/1742-6596/320/1/012065

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