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Finite-temperature properties of the Hubbard chain with bond-charge interaction

Fabrizio Dolcini·Arianna Montorsi
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Abstract

We investigate the one-dimensional Hubbard model with an additional bond-charge interaction, recently considered in the description of compounds that exhibit strong 1D features above the temperature of ordered phases. The partition function of the model is exactly calculated for a value of the bond-charge coupling; the behavior of the specific heat and spin susceptibility as a function of temperature is derived at arbitrary filling, and particularly discussed across the occurring metal-insulator transition. The results show that the bond-charge terms weaken the spin excitations of the system.

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Fabrizio Dolcini, Arianna Montorsi. 2002-04-05. Finite-temperature properties of the Hubbard chain with bond-charge interaction. https://doi.org/10.1103/physrevb.66.075112

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