Excitonic magnet in external field: complex order parameter and spin currents

Abstract

We investigate spin-triplet exciton condensation in the two-orbital Hubbard model close to half filling by means of dynamical mean-field theory. Employing an impurity solver that handles complex off-diagonal hybridization functions, we study the behavior of excitonic condensate in stoichiometric and doped systems subject to external magnetic field. We find a general tendency of the triplet order parameter to lay perpendicular with the applied field and identify exceptions from this rule. For solutions exhibiting k-odd spin textures, we discuss the Bloch theorem which, in the absence of spin-orbit coupling, forbids the appearance of spontaneous net spin current. We demonstrate that the Bloch theorem is not obeyed by the dynamical mean-field theory.

10 pages, 10 figures

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Cited by in corpus (11)

• Collective Modes in Excitonic Magnets: Dynamical Mean-Field Study
• A New Era of Excitonic Insulators
• Exciton condensation in strongly correlated quantum spin Hall insulators
• Spin Seebeck Effect in Nonmagnetic Excitonic Insulators
• Dynamical response and competing orders in two-band Hubbard model
• Spin texture and spin current in excitonic phases of the two-band Hubbard model
• Suppression and revival of long-range ferromagnetic order in the multiorbital Fermi-Hubbard model
• Excitonic Correlations, Spin-State Ordering, and Magnetic-Field Effects in One-Dimensional Two-Orbital Hubbard Model for Spin-Crossover Region
• Strong enhancement of magnetic susceptibility induced by spin-nematic fluctuations in an excitonic insulating system with spin-orbit coupling
• Spin loop-current textures in Hubbard models
• Emergence of pure spin current in doped excitonic magnets