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arXiv · 1207.7124

Half-metallic magnetization plateaux

Zhihao Hao·Oleg A. Starykh
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Abstract

We propose a novel interaction-based route to half-metal state for interacting electrons on two-dimensional lattices. Magnetic field applied parallel to the lattice is used to tune one of the spin densities to a particular commensurate with the lattice value in which the system spontaneously `locks in' via van Hove enhanced density wave state. Electrons of opposite spin polarization retain their metallic character and provide for the half-metal state which, in addition, supports magnetization plateau in a finite interval of external magnetic field. Similar half-metal state is realized in the finite-U Hubbard model on a triangular lattice at 1/3 of the maximum magnetization.

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Zhihao Hao, Oleg A. Starykh. 2012-07-30. Half-metallic magnetization plateaux. https://doi.org/10.1103/physrevb.87.161109

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