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arXiv · 0905.1379

Surface Polaron Formation in the Holstein model

Reza Nourafkan·Massimo Capone·Nasser Nafari
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Abstract

The effect of a solid-vacuum interface on the properties of a strongly coupled electron-phonon system is analyzed using dynamical mean-field theory to solve the Holstein model in a semi-infinite cubic lattice. Polaron formation is found to occur more easily (i.e., for a weaker electron-phonon coupling) on the surface than in the bulk. On the other hand, the metal-insulator transition associated to the binding of polarons takes place at a unique critical strength in the bulk and at the surface.

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Reza Nourafkan, Massimo Capone, Nasser Nafari. 2009-05-09. Surface Polaron Formation in the Holstein model. https://doi.org/10.1103/physrevb.80.155130

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