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Electron Localization in the Insulating State

R. Resta·S. Sorella
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Abstract

The insulating state of matter is characterized by the excitation spectrum, but also by qualitative features of the electronic ground state. The insulating ground wavefunction in fact: (i) sustains macroscopic polarization, and (ii) is localized. We give a sharp definition of the latter concept, and we show how the two basic features stem from essentially the same formalism. Our approach to localization is exemplified by means of a two--band Hubbard model in one dimension. In the noninteracting limit the wavefunction localization is measured by the spread of the Wannier orbitals.

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R. Resta, S. Sorella. 1998-11-03. Electron Localization in the Insulating State. https://doi.org/10.1103/physrevlett.82.370

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