Conductance of a molecular junction mediated by unconventional metal-induced gap states
Institut für Theoretische Physik,
Technische Universität Dresden D-01062 Dresden, Germany
2 Institut für Theoretische Physik, Universität Regensburg D-93040 Regensburg, Germany
Accepted: 28 January 2003
The conductance of a molecular junction is commonly determined by either charge-transfer doping, where alignment of the Fermi energy to the molecular levels is achieved, or tunnelling through the tails of molecular resonances within the highest-occupied and lowest-unoccupied molecular-orbital gap. Here, we present an alternative mechanism where electron transport is dominated by electrode surface states. They give rise to metallization of the molecular bridge and additional, pronounced conductance resonances allowing for substantial tailoring of its electronic properties via, e.g., a gate voltage. This is demonstrated in a field-effect geometry of a fullerene bridge between two metallic carbon nanotubes.
PACS: 73.63.-b – Electronic transport in mesoscopic or nanoscale materials and structures / 85.65.+h – Molecular electronic devices / 73.22.-f – Electronic structure of nanoscale materials: clusters, nanoparticles, nano-tubes, and nanocrystals
© EDP Sciences, 2003