Damping of spinful excitons in LaCoO${}_3$ by thermal fluctuations: Theory and experiment

Abstract

We present Co $L_3$-edge resonant inelastic x-ray scattering (RIXS) of bulk LaCoO${}_3$ across the thermally-induced spin-state crossover around 100~K. Owing to a high energy resolution of 25~meV, we observe unambiguously the dispersion of the intermediate-spin (IS) excitations in the low temperature regime. Approaching the intermediate temperature regime, the IS excitations are damped and the bandwidth is reduced. The observed behavior can be well described by a model of mobile IS excitons with strong attractive interaction, which we solve using dynamical mean-field theory for hard-core bosons. Our results provide a detailed mechanism of how high-spin (HS) and IS excitations interact to establish the physical properties of cobaltite perovskites.

References in corpus (10)

• Continuous-time Monte Carlo methods for quantum impurity models
• The spin state transition in LaCoO${}_3$; revising a revision
• Spin state transition and covalent bonding in LaCoO3
• Correlated bosons on a lattice: Dynamical mean-field theory for Bose-Einstein condensed and normal phases
• Disproportionation and Metallization at Low-Spin to High-Spin Transition in Multiorbital Mott Systems
• Extremely Correlated Fermi Liquids
• Importance of exchange-anisotropy and superexchange for the spin-state transitions in LnCoO3 (Ln=La,Y,RE) cobaltates
• Coulomb correlations intertwined with spin and orbital excitations in LaCoO${}_3$
• Excitonic magnetism in $d^6$ perovskites
• Pressure-induced spin-state ordering in Sr${}_2$CoO${}_3$F

Cited by in corpus (5)

• Two Spin-State Crystallizations in LaCoO${}_3$
• Photo-induced insulator-to-metal transition and coherent acoustic phonon propagation in LaCoO${}_3$ thin films explored by femtosecond pump-probe ellipsometry
• A review on magnetic field induced spin crossover in LaCoO${}_3$ up to 600 T
• Symmetry-resolved elastic anomalies in spin-crossover cobaltite LaCoO${}_3$
• Optical signatures of strain-induced ferromagnetism in LaCoO${}_3$ thin film