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Lattice polarization effects on electron-gas charge densities in ionic superlattices

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 نشر من قبل D. R. Hamann
 تاريخ النشر 2006
  مجال البحث فيزياء
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The atomic-level control achievable in artificially-structured oxide superlattices provides a unique opportunity to explore interface phases of matter including high-density 2D electron gases. Electronic-structure calculations show that the charge distribution of the 2D gas is strongly modulated by electron-phonon interactions with significant ionic polarization. Anharmonic finite-temperature effects must be included to reproduce experiment. Density functional perturbation theory is used to parameterize a simple model introduced to represent these effects and predict temperature dependencies.

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