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arXiv · 0906.4386

Electronic and magnetic properties of metallic phases under coexisting short-range interaction and diagonal disorder

Hiroshi Shinaoka·Masatoshi Imada
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Abstract

We study a three-dimensional Anderson-Hubbard model under the coexistence of short-range interaction and diagonal disorder within the Hartree-Fock approximation. We show that the density of states at the Fermi energy is suppressed in the metallic phases near the metal-insulator transition as a proximity effect of the soft Hubbard gap in the insulating phases. The transition to the insulator is characterized by a vanishing DOS in contrast to formation of a quasiparticle peak at the Fermi energy obtained by the dynamical mean field theory in pure systems. Furthermore, we show that there exist frozen spin moments in the paramagnetic metal.

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Hiroshi Shinaoka, Masatoshi Imada. 2010-08-23. Electronic and magnetic properties of metallic phases under coexisting short-range interaction and diagonal disorder. https://doi.org/10.1143/jpsj.79.094711

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