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Spatial decay of the single-particle density matrix in tight-binding metals: +AFwAXA- analytic results in two dimensions

S. N. Taraskin·P. A. Fry·Xiadong Zhang·D. A. Drabold·S. R. Elliott
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Abstract

Analytical results for the asymptotic spatial decay of the density matrix $+AFw-rho({+AFw-bf r},{+AFw-bf r^+AFw-prime})$ in the tight-binding model of the two-dimensional metal are presented. In various dimensions D, it is found analytically and numerically that the density matrix decays with distance according to the power law, $+AFw-rho({+AFw-bf r},{+AFw-bf r^+AFw-prime}) +AFw-propto |{+AFw-bf r}-{+AFw-bf r^+AFw-prime}|^{-(D+-1)/2}$.

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S. N. Taraskin, P. A. Fry, Xiadong Zhang, D. A. Drabold, S. R. Elliott. 2002-09-19. Spatial decay of the single-particle density matrix in tight-binding metals: +AFwAXA- analytic results in two dimensions. https://doi.org/10.1103/physrevb.66.233101

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