Nonequilibrium inelastic electronic transport: Polarization effects and vertex corrections to the self-consistent Born approximation

Article

关键词: CURRENT-VOLTAGE CHARACTERISTICS;    TUNNELING SPECTROSCOPY;    MOLECULAR JUNCTIONS;    CHARGE-TRANSPORT;    CONDUCTANCE;    WIRES;    TRANSISTORS;    MICROSCOPY;    SCALE;    RULES;   

DOI  :  10.1103/PhysRevB.84.085433

来源: SCIE

【 摘 要 】

We study the effect of electron-vibron interactions on the inelastic transport properties of single-molecule nanojunctions. We use the nonequilibrium Green's functions technique and a model Hamiltonian to calculate the effects of second-order diagrams [double-exchange (DX) and dressed-phonon (DPH) diagrams] on the electron-vibration interaction and consider their effects across the full range of parameter space. The DX diagram, corresponding to a vertex correction, introduces an effective dynamical renormalization of the electron-vibron coupling in both the purely inelastic and the inelastic-resonant features of the inelastic electron tunneling spectrum. The purely inelastic features correspond to an applied bias around the energy of a vibron, while the inelastic-resonant features correspond to peaks (resonance) in the conductance. The DPH diagram affects only the inelastic resonant features. We also discuss the circumstances in which the second-order diagrams may be approximated in the study of more complex model systems.

【 授权许可】

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