Density of States in the t-Hubbard Model: Exact Diagonalisation Results
نویسندگان
چکیده
We calculated the density of states in a Hubbard mortel with nearest and next nearest neighbour hopping. Using an exact diagonalisation technique, we examined this mortel in a wide area of parameters. The density of states was calculated for dilferent fillings and for positive and negative interaction U. The additional hopping to the next nearest neighbour sites has dilferent elfects on the gap between the particle and hole spectrum compared to the
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