Nonlinear current-voltage characteristics of Pt nanowires and nanowire transistors fabricated by electron-beam deposition

Pt/C composite nanowires and nanowire-transistors were fabricated using the technique of EBID. The current-voltage characteristics of the granular nanowires were found to be strongly nonlinear at 4.2 K, and evidence for this nonlinearity was found to persist to room temperature. A voltage gap of order 0.1-0.2 V was observed at the lowest temperatures. This feature was attributed to single-electron tunneling via Pt nanocrystals that form in the wires during their fabrication. In order to further explore this possibility, the nanowires were incorporated into three-terminal transistor structures. Evidence for a gate-induced modulation of their voltage gap was found. Gate leakage, possibly via surface conduction, prevented the observation of clear Coulomb oscillations.