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arXiv · 0712.1354

Localized polarons and doorway vibrons in finite quantum structures

H. Fehske·G. Wellein·J. Loos·A. R. Bishop
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Abstract

We consider transport through finite quantum systems such as quantum barriers, wells, dots or junctions, coupled to local vibrational modes in the quantal regime. As a generic model we study the Holstein-Hubbard Hamiltonian with site-dependent potentials and interactions. Depending on the barrier height to electron-phonon coupling strength ratio and the phonon frequency we find distinct opposed behaviors: Vibration-mediated tunneling or intrinsic localization of (bi)polarons. These regimes are strongly manifested in the density correlations, mobility, and optical response calculated by exact numerical techniques.

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H. Fehske, G. Wellein, J. Loos, A. R. Bishop. 2008-02-23. Localized polarons and doorway vibrons in finite quantum structures. https://doi.org/10.1103/physrevb.77.085117

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