ab initio modeling of open systems: charge transfer, electron conduction, and molecular switching of a C_{60} device

摘要

We present an {\it ab initio} analysis of electron conduction through a$C_{60}$ molecular device. Charge transfer from the device electrodes to themolecular region is found to play a crucial role in aligning the lowestunoccupied molecular orbital (LUMO) of the $C_{60}$ to the Fermi level of theelectrodes. This alignment induces a substantial device conductance of $\sim2.2 \times (2e^2/h)$. A gate potential can inhibit charge transfer andintroduce a conductance gap near $E_F$, changing the current-voltagecharacteristics from metallic to semi-conducting, thereby producing a fieldeffect molecular current switch.