Robust negative differential conductance and enhanced shot noise in transport through a molecular transistor with vibration assistance

Abstract

In this paper, we analyze vibration-assisted sequential tunneling (including current-voltage characteristics and zero-frequency shot noise) through a molecular quantum dot with two electronic orbitals asymmetrically coupled to the internal vibration. We employ rate equations for the case of equilibrated phonons, and strong Coulomb blockade. We find that a system with a strongly phonon-coupled ground state orbital and weakly phonon-coupled excited state orbital exhibits strong negative differential conductance; and it also shows super-Poissonian current noise. We discuss in detail the reasons and conditions for the appearance of negative differential conductance.

6 pages, 6 figures, and 1 table

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Cited by in corpus (3)

• Full counting statistics of a single-molecular quantum dot
• Full counting statistics of phonon-assisted Andreev tunneling through a quantum dot coupled to normal and superconducting leads
• Counting statistics of tunneling through a single molecule: effect of distortion and displacement of vibrational potential surface