Electron Transport Through Molecules: Gate Induced Polarization and Potential Shift

Abstract

We analyze the effect of a gate on the conductance of molecules by separately evaluating the gate-induced polarization and the potential shift of the molecule relative to the leads. The calculations use ab initio density functional theory combined with a Green function method for electron transport. For a general view, we study several systems: (1) atomic chains of C or Al sandwiched between Al electrodes, (2) a benzene molecule between Au leads, and (3) (9,0) and (5,5) carbon nanotubes. We find that the polarization effect is small because of screening, while the effect of the potential shift is significant, providing a mechanism for single-molecule transistors.

4 pages, 4 figures

References in corpus (8)

• The SIESTA method for ab initio order-N materials simulation
• Efficient index handling of multidimensional periodic boundary conditions
• ab initio modeling of open systems: charge transfer, electron conduction, and molecular switching of a C_{60} device
• Electron Transport Through Molecules: Self-consistent and Non-self-consistent Approaches
• Electrical Nanoprobing of Semiconducting Carbon Nanotubes using an Atomic Force Microscope
• Contact Atomic Structure and Electron Transport Through Molecules
• Electrostatic potential profiles of molecular conductors
• Local gating of carbon nanotubes

Cited by in corpus (5)

• Density functional calculations of nanoscale conductance
• Electron density and transport in top-gated graphene nanoribbon devices: First-principles Green function algorithms for systems containing large number of atoms
• Green function techniques in the treatment of quantum transport at the molecular scale
• Coulomb blockade in electron transport through a C${}_{60}$ molecule from first principles
• Quantum Interference Controlled Molecular Electronics