Electromechanical instability in vibrating quantum dots with effectively negative charging energy
arXiv:0907.3041 · doi:10.1103/PhysRevB.80.195103
Abstract
In quantum dots or molecules with vibrational degrees of freedom the electron-vibron coupling renormalizes the electronic charging energy. For sufficiently strong coupling, the renormalized charging energy can become negative. Here, we discuss an instability towards adding or removing an arbitrary number of electrons when the magnitude of the renormalized charging energy exceeds the single-particle level spacing. We show that the instability is regularized by the anharmonic contribution to the vibron energy. The resulting effective charging energy as a function of the electron number has a double-well structure causing a variety of novel features in the Coulomb blockade properties.
8 pages, 10 Figs
References in corpus (16)
- A tunable carbon nanotube electromechanical oscillator
- Coupling of Spin and Orbital Motion of Electrons in Carbon Nanotubes
- Cooling a nanomechanical resonator with quantum back-action
- Franck-Condon blockade and giant Fano factors in transport through single molecules
- Electrical generation and absorption of phonons in carbon nanotubes
- Franck-Condon blockade in suspended carbon nanotube quantum dots
- Vibrational sidebands and dissipative tunneling in molecular transistors
- Theory of the Franck-Condon blockade regime
- Tunneling in suspended carbon nanotubes assisted by longitudinal phonons
- Many Body Effects on the Transport Properties of Single-Molecule Devices
- Shot Noise of a Quantum Shuttle
- Quantum transport through a deformable molecular transistor
- Distortion blockade in classical nano-electromechanical resonator
- Nonequilibrium charge-Kondo transport through negative-U molecules
- Electron-vibron coupling in suspended carbon nanotube quantum dots
- Magnetoconductance through a vibrating molecule in the Kondo regime