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Momentum distribution of itinerant electrons in the one-dimensional Falicov-Kimball model

Pavol Farkasovsky
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Abstract

The momentum distribution $n_k$ of itinerant electrons in the one-dimensional Falicov-Kimball model is calculated for various ground-state phases. In particular, we examine the periodic phases with period two, three and four (that are ground-states for all Coulomb interactions) as well as the phase separated states (that are ground states for small Coulomb interactions). For all periodic phases examined the momentum distribution is a smooth function of $k$ with no sign of any discontinuity or singular behavior at the Fermi surface $k=k_F$. An unusual behavior of $n_k$ (a local maximum) is found at $k=3k_F$ for electron concentrations outside half-filling. For the phase separated ground states the momentum distribution $n_k$ exhibits discontinuity at $k=k_0 < k_F$. This behavior is interpreted in terms of a Fermi liquid.

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Pavol Farkasovsky. 2003-12-18. Momentum distribution of itinerant electrons in the one-dimensional Falicov-Kimball model. https://doi.org/10.1142/s0217979203023021

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