Screening-induced negative differential conductance in the Franck-Condon blockade regime

E. Perfetto; G. Stefanucci

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arXiv · 1307.7527

Screening-induced negative differential conductance in the Franck-Condon blockade regime

E. Perfetto·G. Stefanucci

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Abstract

Screening effects in nanoscale junctions with strong electron-phonon coupling open new physical scenarios. We propose an accurate many-body approach to deal with the simultaneous occurrence of the Franck-Condon blockade and the screening-induced enhancement of the polaron mobility. We derive a transparent analytic expression for the electrical current: transient and steady-state features are directly interpreted and explained. Moreover, the interplay between phononic and electronic excitations gives rise to a novel mechanism of negative differential conductance. Experimental setup to observe this phenomenon are discussed.

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E. Perfetto, G. Stefanucci. 2013-07-29. Screening-induced negative differential conductance in the Franck-Condon blockade regime. https://arxiv.org/abs/1307.7527

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