Quantum topological transitions and spinons in metallic ferro- and antiferromagnets

Publication date: Available online 29 January 2019Source: Physics Letters AAuthor(s): V.Yu. IrkhinAbstractAn 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.

Source: Physics Letters A - January 30, 2019 Category: Physics Source Type: research