Vibration-mediated resonant tunneling and shot noise through a molecular quantum dot

Abstract

Motivated by a recent experiment on nonlinear tunneling in a suspended Carbon nanotube connected to two normal electrodes [S. Sapmaz, {\it et al}., Phys. Rev. Lett. {\bf 96}, 26801 (2006)], we investigate nonequilibrium vibration-mediated sequential tunneling through a molecular quantum dot with two electronic orbitals asymmetrically coupled to two electrodes and strongly interacting with an internal vibrational mode, which is itself weakly coupled to a dissipative phonon bath. For this purpose, we establish rate equations using a generic quantum Langevin equation approach. Based on these equations, we study in detail the current-voltage characteristics and zero-frequency shot noise, paying special attention to the advanced or postponed of the appearance of negative differential conductance and super-Poissonian current noise resulting from electron-phonon-coupling induced {\em selective unidirectional cascades of single-electron transitions}.

11 pages, 7 figures

References in corpus (9)

• Franck-Condon blockade and giant Fano factors in transport through single molecules
• The Kondo effect in C${}_{60}$ single-molecule transistors
• Electrical generation and absorption of phonons in carbon nanotubes
• Inelastic electron tunneling via molecular vibrations in single-molecule transistors
• Tunneling in suspended carbon nanotubes assisted by longitudinal phonons
• Full counting statistics of strongly non-Ohmic transport through single molecules
• Effects of charge-dependent vibrational frequencies and anharmonicities in transport through molecules
• Three-terminal scanning tunneling spectroscopy of suspended carbon nanotubes
• Anomalous suppression of the shot noise in a nanoelectromechanical system

Cited by in corpus (6)

• Resonant Electron Transport in Single-Molecule Junctions: Vibrational Excitation, Rectification, Negative Differential Resistance and Local Cooling
• Coherent properties of nano-electromechanical systems
• Vibrational effects in charge transport through a molecular double quantum dot
• Localized polarons and doorway vibrons in finite quantum structures
• Full counting statistics of phonon-assisted Andreev tunneling through a quantum dot coupled to normal and superconducting leads
• Interference and shot noise in a degenerate Anderson-Holstein model