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Transport through a molecular quantum dot in the polaron crossover regime

Alex Zazunov·Thierry Martin
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Abstract

We consider resonant transport through a molecular quantum dot coupled to a local vibration mode. Applying the non-equilibrium Green function technique in the polaron representation, we develop a non-perturbative scheme to calculate the electron spectral function of the molecule in the regime of intermediate electron-phonon coupling. With increasing tunneling coupling to the leads, correlations between polaron clouds become more important at relatively high temperature leading to a strong sharpening of the peak structure in the spectral function. The detection of such features in the current-voltage characteristics is briefly discussed.

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Alex Zazunov, Thierry Martin. 2007-03-23. Transport through a molecular quantum dot in the polaron crossover regime. https://doi.org/10.1103/physrevb.76.033417

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