Charge pumping in strongly-coupled molecular quantum dots

Abstract

The interaction between electrons and the vibrational degrees of freedom of a molecular quantum dot can lead to an exponential suppression of the conductance, an effect which is commonly termed Franck-Condon blockade. Here, we investigate this effect in a quantum dot driven by time-periodic gate voltages and tunneling amplitudes using nonequilibrium Green's functions and a Floquet expansion. Building on previous results showing that driving can lift the Franck-Condon blockade, we investigate driving protocols which can be used to pump charge across the quantum dot. In particular, we show that due to the strongly coupled nature of the system, the pump current at resonance is an exponential function of the drive strength.

9 pages, 6 figures

References in corpus (13)

• A tunable carbon nanotube electromechanical oscillator
• Franck-Condon blockade and giant Fano factors in transport through single molecules
• Carbon nanotubes as ultra-high quality factor mechanical resonators
• Franck-Condon blockade in suspended carbon nanotube quantum dots
• Theory of the Franck-Condon blockade regime
• Tunneling in suspended carbon nanotubes assisted by longitudinal phonons
• Correlated electron systems periodically driven out of equilibrium: Floquet + DMFT formalism
• Vibrational Sidebands and Kondo-effect in Molecular Transistors
• Nonadiabatic Electron Pumping: Maximal Current with Minimal Noise
• Charge transfer statistics of a molecular quantum dot with strong electron-phonon interaction
• Non adiabatic features of electron pumping through a quantum dot in the Kondo regime
• Phase coherence, inelastic scattering, and interaction corrections in pumping through quantum dots
• Lifting the Franck-Condon blockade in driven quantum dots