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Critical Spectral Statistics at the Metal-Insulator Transition in Interacting Fermionic Systems

Philippe Jacquod
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Abstract

The spectral properties of a disordered system with few interacting three-dimensional spinless fermions are investigated. We show the existence of a critical spacings distribution which is invariant upon increase of the system size, but strongly depends on the number of particles. At the critical point, we report a substantial decrease of the degree of level repulsion as the number of particles increases indicating a decrease of nearest level correlations associated with the sparsity of the Hamiltonian matrix.

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Philippe Jacquod. 1998-07-09. Critical Spectral Statistics at the Metal-Insulator Transition in Interacting Fermionic Systems. https://doi.org/10.1103/physrevlett.81.1913

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