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Statistics of energy spectra of a strongly disordered system of interacting electrons

R. Berkovits·B. I. Shklovskii
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Abstract

Statistics of many particle energy levels of a finite two-dimensional system of interacting electrons is numerically studied. It is shown that the statistics of these levels undergoes a Poisson to Wigner crossover as the strength of the disorder is decreased. This transition occurs at a similar strength of disorder as the one-electron delocalization crossover in a finite 2d system and develops almost simultaneously at all energies. We interpret this crossover in terms of delocalization in the space of occupation numbers of strongly bound and compact electron-hole pairs (excitons).

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R. Berkovits, B. I. Shklovskii. 1998-07-10. Statistics of energy spectra of a strongly disordered system of interacting electrons. https://doi.org/10.1088/0953-8984%2F11%2F3%2F017

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