SciPost Physics

SciPost Phys. 10, 077 (2021) · published 26 March 2021

• doi: 10.21468/SciPostPhys.10.3.077
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Abstract

Utilizing the unbiased time-dependent density-matrix renormalization group technique, we examine the photoemission spectra in the extended Falicov-Kimball model at zero and finite temperatures, particularly with regard to the excitonic insulator state most likely observed in the quasi-one-dimensional material Ta$_2$NiSe$_5$. Working with infinite boundary conditions, we are able to simulate all dynamical correlation functions directly in the thermodynamic limit. For model parameters best suited for Ta$_2$NiSe$_5$ the photoemission spectra show a weak but clearly visible two-peak structure, around the Fermi momenta $k\simeq\pm k_{\rm F}$, which suggests that Ta$_2$NiSe$_5$ develops an excitonic insulator of BCS-like type. At higher temperatures, the leakage of the conduction-electron band beyond the Fermi energy becomes distinct, which provides a possible explanation for the bare non-interacting band structure seen in time- and angle-resolved photoemission spectroscopy experiments.

• Ejima et al., Photoinduced pairing in Mott insulators
  SciPost Phys. Proc., 009 (2023) [Crossref]
• Farkašovský, Hartree-Fock exploration of electronic ferroelectricity, valence transitions, and metal-insulator transitions in the extended Falicov-Kimball model
  Phys. Rev. B 108, 075161 (2023) [Crossref]
• Do et al., Excitonic condensation state in the assistance of the adiabatic and anti-adiabatic phonons
  J. Phys.: Condens. Matter 34, 165602 (2022) [Crossref]
• Sim et al., Nonlinear spectroscopy of bound states in perturbed Ising spin chains
  Phys. Rev. B 107, L100404 (2023) [Crossref]
• Farkašovský, Influence of magnetic field on the electronic ferroelectricity in the extended Falicov-Kimball model
  J. Phys.: Condens. Matter 36, 085601 (2024) [Crossref]
• Sugimoto et al., Pump-probe spectroscopy of the one-dimensional extended Hubbard model at half filling
  Phys. Rev. B 108, 195128 (2023) [Crossref]
• Ejima et al., Photoinduced metallization of excitonic insulators
  Phys. Rev. B 105, 245126 (2022) [Crossref]
• Ejima et al., Nonequilibrium dynamics in pumped Mott insulators
  Phys. Rev. Research 4, L012012 (2022) [Crossref]
• Udono et al., Excitonic effects on high-harmonic generation in Mott insulators
  Phys. Rev. B 105, L241108 (2022) [Crossref]