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arXiv · 1102.0837

Excitonic resonances in the 2D extended Falicov-Kimball model

Van-Nham Phan·Holger Fehske·Klaus W. Becker
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Abstract

Using the projector-based renormalization method we investigate the formation of the excitonic insulator phase in the two-dimensional (2D) spinless Falicov-Kimball model with dispersive $f$ electrons and address the existence of excitonic bound states at high temperatures on the semiconductor side of the semimetal-semiconductor transition. To this end we calculate the imaginary part of the dynamical electron-hole pair susceptibility and analyze the wave-vector and energy dependence of excitonic resonances emerging in the band gap. We thereby confirm the existence of the exciton insulator and its exciton environment within a generic two-band lattice model with local Coulomb attraction.

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Van-Nham Phan, Holger Fehske, Klaus W. Becker. 2011-06-19. Excitonic resonances in the 2D extended Falicov-Kimball model. https://doi.org/10.1209/0295-5075%2F95%2F17006

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