A photoresponsive single electron transistor prepared from oligothiophene molecules and gold nanoparticles in a nanogap electrode

Abstract

Gold nanoparticle-oligothiophene pentamer networks were prepared in a nanogap electrode and their photoresponsive and conductive properties were measured. Coulomb diamond appeared in the differential conductance map of the device at cryogenic temperatures, indicating that the device worked as a single electron transistor. Upon irradiation with UV light, the current showed discontinuous changes. The I-VSD curve and differential conductance mapping before and after irradiation showed that the abrupt changes in current can be explained by a shift in the potential of the Coulomb island.