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Polaronic transport through molecular quantum dots: charging-induced NDR and rectifying behavior

Kamil Walczak
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Abstract

Here we study the polaronic transport through molecules weakly connected to metallic electrodes in the nonlinear response regime. Molecule itself is treated as a quantum dot with discrete energy levels, its connection to the electrodes is described within the wide-band approximation, while the charging is incorporated by means of the self-consistent potential. Nonperturbative computational scheme, used in this work, is based on the Green's function theory within the framework of mapping technique (GFT-MT). This method transforms the many-body electron-phonon interaction problem into a one-body multi-channel single-electron scattering problem with occupation of polaron levels calculated in the self-consistent way. In particular, three different phenomena as a result of charging in polaronic transport via discrete quantum states are discussed in detail: the suppression of the current at higher voltages, negative differential resistance (NDR effect), and rectification.

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Kamil Walczak. 2006-02-08. Polaronic transport through molecular quantum dots: charging-induced NDR and rectifying behavior. https://arxiv.org/abs/cond-mat/0602213

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