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Filling dependence of the Mott transition in the degenerate Hubbard model

Erik Koch·Olle Gunnarsson·Richard M. Martin
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Abstract

Describing the doped Fullerenes using a generalized Hubbard model, we study the Mott transition for different integer fillings of the t_1u band. We use the opening of the energy-gap E_g as a criterion for the transition. E_g is calculated as a function of the on-site Coulomb interaction U using fixed-node diffusion Monte Carlo. We find that for systems with doping away from half-filling the Mott transitions occurs at smaller U than for the half-filled system. We give a simple model for the doping dependence of the Mott transition.

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Erik Koch, Olle Gunnarsson, Richard M. Martin. 1999-05-25. Filling dependence of the Mott transition in the degenerate Hubbard model. https://doi.org/10.1103/physrevb.60.15714

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