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Spectral functions of the Falicov-Kimball model with electronic ferroelectricity

Wei-Guo Yin·W. N. Mei·Chun-Gang Duan·Hai-Qing Lin·J. R. Hardy
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Abstract

We calculate the angular resolved photoemission spectrum of the Falicov-Kimball model with electronic ferroelectricity where $d$- and $f$-electrons have different hoppings. In mix-valence regimes, the presence of strong scattering processes between $d$-$f$ excitons and a hole, created by emission of an electron, leads to the formation of pseudospin polarons and novel electronic structures with bandwidth scaling with that of $d$-$f$ excitons. Especially, in the two-dimensional case, we find that flat regions exist near the bottom of the quasiparticle band in a wide range of the $d$- and $f$-level energy difference.

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Wei-Guo Yin, W. N. Mei, Chun-Gang Duan, Hai-Qing Lin, J. R. Hardy. 2003-02-26. Spectral functions of the Falicov-Kimball model with electronic ferroelectricity. https://doi.org/10.1103/physrevb.68.075111

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