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arXiv · 1903.11003

Quantum topological transitions and spinons in metallic ferro- and antiferromagnets

V. Yu. Irkhin
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Abstract

An effective Hamiltonian describing fluctuation effects in the magnetic phases of the Hubbard model in terms of spinon excitations is derived. A comparison of spin-rotational Kotliar-Ruckenstein slave boson and Ribeiro-Wen dopon representations is performed. The quantum transition into the half-metallic ferromagnetic state with vanishing of spin-down Fermi surface is treated as the topological Lifshitz transition in the quasimomentum space. The itinerant-localized magnetism transitions and Mott transition in antiferromagnetic state are considered in the topological context. Related metal-insulator transitions in Heusler alloys are discussed.

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V. Yu. Irkhin. 2019-03-26. Quantum topological transitions and spinons in metallic ferro- and antiferromagnets. https://doi.org/10.1016/j.physleta.2019.01.055

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