Abstract
The spinless Falicov-Kimball model for electronically driven metal-insulator and valence transitions is studied using exact numerical calculations. It is shown that in the pressure induced case the model undergoes a few (discrete) intermediate valence transitions, while valence transitions as a function of temperature are always continuous. We demonstrate that these results are independent of finite-size effects. Interesting consequences of this picture of valence changes can be found furthermore under the assumption that thef-level position may fluctuate (due to some additional interactions) about its average value. Then the model is capable to describe a transition from an inhomogeneous intermediate valence state into a homogeneous intermediate valence state as well as the semiconductor-metal transition.
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Farkašovský, P. Electronic phase transitions in the spinless Falicov-Kimball model. Z. Phys. B - Condensed Matter 99, 77–82 (1995). https://doi.org/10.1007/s002570050013
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DOI: https://doi.org/10.1007/s002570050013