Nanoampere charge pump by single-electron ratchet using silicon nanowire metal-oxide-semiconductor field-effect transistor

Nanoampere single-electron pumping is presented at 20 K using a single-electron ratchet comprising silicon nanowire metal-oxide-semiconductor field-effect transistors. The ratchet features an asymmetric potential with a pocket that captures single electrons from the source and ejects them to the drain. Directional single-electron transfer is achieved by applying one ac signal with the frequency up to 2.3 GHz. We find anomalous shapes of current steps which can be ascribed to nonadiabatic electron capture. (c) 2008 American Institute of Physics.