Coulomb repulsion versus Hubbard repulsion in a disordered chain

Franck Selva; Jean-Louis Pichard

doi:10.1007/pl00011105

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arXiv · cond-mat/0003338

Coulomb repulsion versus Hubbard repulsion in a disordered chain

Franck Selva·Jean-Louis Pichard

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Abstract

We study the difference between on site Hubbard and long range Coulomb repulsions for two interacting particles in a disordered chain. While Hubbard repulsion can only yield weak critical chaos with intermediate spectral statistics, Coulomb repulsion can drive the two particle system to quantum chaos with Wigner-Dyson spectral statistics. For intermediate strengths U of the two repulsions in one dimension, there is a crossover regime where delocalization and spectral rigidity are maximum, whereas the limits of weak and strong U are characterized by a stronger localization and uncorrelated energy levels.

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Franck Selva, Jean-Louis Pichard. 2000-03-20. Coulomb repulsion versus Hubbard repulsion in a disordered chain. https://doi.org/10.1007/pl00011105

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