Filling dependence of the Mott transition in the degenerate Hubbard model.

Koch E., Gunmarsson O., Martin R.M.

Describing the doped Fullerenes using a generalized Hubbard model, we study the Mott transition for different integer fillings of the t1u band. We use the opening of the energy-gap Eg as a criterion for the transition. Eg 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.

Physical Review B, 60 15714-20, 1999.

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