physica status solidi (b)

On the density of states at the fermi level for normal systems

Ulrich Behn, H. Zinke

Published Dec 1, 1977• 2 citations

Abstract

Abstract In the single‐site and the nearest‐neighbour approximation, respectively, the density of electronic states at the Fermi level for normal systems at T = 0 is considered as a functional of the unperturbed density of states. For electron–hole symmetric systems, e.g. the half‐filled‐band Hubbard model, the density of states at the Fermi level in a normal single‐site approximation is either equal to the unperturbed value or vanishes. The expected gradual change in the density of states can be obtained in the nearest‐neighbour approximation.

DOI: 10.1002/pssb.2220840229

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