Finite-temperature properties of excitonic condensation in the extended Falicov-Kimball model: Cluster mean-field-theory approach

Abstract

We study the electron-hole pair (or excitonic) condensation in the extended Falicov-Kimball model at finite temperatures based on the cluster mean-field-theory approach, where we make the grand canonical exact-diagonalization analysis of small clusters using the sine-square deformation function. We thus calculate the ground-state and finite-temperature phase diagrams of the model, as well as its optical conductivity and single-particle spectra, thereby clarifying how the preformed pair states appear in the strong-coupling regime of excitonic insulators. We compare our results with experiment on Ta${}_2$NiSe${}_5$.

5 pages, 5 figures

References in corpus (4)

• Excitonic Bose-Einstein condensation in Ta2NiSe5 above room temperature
• Phase diagram and spin correlations of the Kitaev-Heisenberg model: Importance of quantum effects
• Noncollinear Magnetic Order Stabilized by Entangled Spin-Orbital Fluctuations
• Orbital diamagnetic susceptibility in excitonic condensation phase

Cited by in corpus (7)

• Ultrafast melting and recovery of collective order in the excitonic insulator Ta${}_2$NiSe${}_5$
• A New Era of Excitonic Insulators
• Finite-temperature photoemission in the extended Falicov-Kimball model: a case study for Ta${}_2$NiSe${}_5$
• Third-harmonic generation in excitonic insulators
• Sine-square deformed mean-field theory
• Excitonic insulator phase and dynamics of condensate in a topological one-dimensional model
• Magnetic-field effect on excitonic condensation emergent in extended Falicov-Kimball model