Excitonic ordering in strongly correlated spin crossover systems: induced magnetism and excitonic excitation spectrum

Abstract

The effects associated with interatomic hoppings of excitons and the excitonic Bose condensate formation in the strongly correlated spin crossover systems are considered in the framework of the effective Hamiltonian for the two-band Kanamori model. The appearance of antiferromagnetic ordering due to the exciton order is found even in the absence of interatomic exchange interaction. The spectrum of excitonic excitations is calculated at various points of the "temperature vs. crystal field" phase diagram. Outside the region of exciton ordering, the spectrum has a gap, which vanishes at the boundary of the exciton condensate phase. The non-uniform spectral weight distribution over the Brillouin zone is found. The role of electron-phonon interaction is discussed as well.

arXiv comment10 pages, 10 figures

References in corpus (25)

• Bose-Einstein Condensation in Magnetic Insulators
• Quantum Criticality
• Excitonic Magnetism in Van Vleck-type d^4 Mott Insulators
• Field- and pressure-induced magnetic quantum phase transitions in TlCuCl_3
• High-spin to low-spin and orbital polarization transitions in multiorbital Mott systems
• Higgs mode and its decay in a two dimensional antiferromagnet
• Excitonic condensation in systems of strongly correlated electrons
• Photo-induced enhancement of excitonic order
• Magnetic properties and spin waves of bilayer magnets in a uniform field
• Raman scattering from Higgs mode oscillations in the two-dimensional antiferromagnet Ca${}_2$RuO${}_4$
• Excitonic Instability at the Spin-State Transition in the Two-Band Hubbard Model
• Spin state ordering of strongly correlating LaCoO${}_3$ induced at ultrahigh magnetic fields
• Phase diagram and collective excitation in excitonic insulator: from the orbital physics viewpoint
• A cascade of magnetic field induced spin transitions in LaCoO3
• Field-induced exciton condensation in LaCoO3
• Roles of Hund's rule coupling in excitonic density-wave states
• Magnetic field effects in a correlated electron system with spin-state degree of freedom - Implication of an excitonic insulator -
• Excitonic order at strong-coupling: pseudo-spins, doping, and ferromagnetism
• Mechanism of spin crossover in LaCoO3 resolved by shape magnetostriction in pulsed magnetic fields
• Width of the longitudinal magnon in the vicinity of the O(3) quantum critical point
• Spin-state transition and phase separation in multi-orbital Hubbard model
• In-gap excitation effect on a superexchange in La2CuO4 by creating nonequilibrium photoexcited centers
• Spin-state Crossover Model for the Magnetism of Iron Pnictides
• Magnetic-field-induced spin crossover of Y-doped Pr${}_{0.7}$Ca${}_{0.3}$CoO${}_3$
• Spin crossover: the quantum phase transition induced by high pressure