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

We have fabricated Pt/C composite nanowires and nanowire transistors, using the technique of electron-beam-induced deposition. The current-voltage characteristics of the granular nanowires are strongly nonlinear at 4.2 K, and evidence for this nonlinearity is found to persist to room temperature. A voltage gap of order 0.1–0.2 V is observed at the lowest temperatures, and we suggest that this feature is consistent with single-electron tunneling via Pt nanocrystals that form in the wires during their fabrication. In order to further explore this possibility, we incorporate the nanowires into three-terminal transistor structures and find evidence for a gate-induced modulation of their voltage gap.