Molecular-scale rectifying diodes based on Y-junction carbon nanotubes

The first experimental Y-junction carbon nanotube transport measurements are reported. These carbon nanotube heterojunctions were fabricated using a recently developed template growth method. Two-terminal I-V characteristics of the Y-junctions display rectification at room temperature making these structures useful as molecular-scale diodes. The observed behavior is consistent with the asymmetry caused by the change in tube diameter across the junction. Possible mechanisms which could account for the transport properties of the Y-junction are discussed.