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

D. R. Hamann·D. A. Muller·H. Y. Hwang
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Abstract

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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D. R. Hamann, D. A. Muller, H. Y. Hwang. 2006-04-12. Lattice polarization effects on electron-gas charge densities in ionic superlattices. https://doi.org/10.1103/physrevb.73.195403

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