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Charge-density-wave order parameter of the Falicov-Kimball model in infinite dimensions

Ling Chen·B. A. Jones·J. K. Freericks
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Abstract

In the large-U limit, the Falicov-Kimball model maps onto an effective Ising model, with an order parameter described by a BCS-like mean-field theory in infinite dimensions. In the small-U limit, van Dongen and Vollhardt showed that the order parameter assumes a strange non-BCS-like shape with a sharp reduction near T approx T_c/2. Here we numerically investigate the crossover between these two regimes and qualitatively determine the order parameter for a variety of different values of U. We find the overall behavior of the order parameter as a function of temperature to be quite anomalous.

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Ling Chen, B. A. Jones, J. K. Freericks. 2003-06-16. Charge-density-wave order parameter of the Falicov-Kimball model in infinite dimensions. https://doi.org/10.1103/physrevb.68.153102

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