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Fermi-linearization scheme for itinerant electrons with Clifford variables

Arianna Montorsi·Alessandro Pelizzola
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Abstract

We propose here an alternative interpretation of the fermi-linarization approach to interacting electron systems, based on the requirement that the coefficients of the linearized operators are Clifford-like variables, whose anticommutator equals an unknown constant $c$. We apply the approximation to the Falicov-Kimball model, explicitly solving the self-consistency equation for the unknown, which turns out to behave as an order parameter. We discuss its relation with a metal-insulator transition and some thermodynamical quantities. In particular we show that our approximation in the $T=0$ limit reproduces exactly the Gutzwiller results for the Hubbard model.

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Arianna Montorsi, Alessandro Pelizzola. 1992-09-16. Fermi-linearization scheme for itinerant electrons with Clifford variables. https://doi.org/10.1088/0305-4470%2F25%2F22%2F009

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