Current Oscillations and Negative Resistances in Crossed Carbon Nanotubes Suspended Over a Dielectric Trench

Ahmad, M. Al; Dragoman, D.; Dragoman, M.; Plana, R.; Ting, J. -H.; Huang, F. -Y.; Li, T. -L.

Current Oscillations and Negative Resistances in Crossed Carbon Nanotubes Suspended Over a Dielectric Trench

Authors

Description

An oscillatory dependence of the drain current on the drain voltage is found in a nanostructure consisting of two crossing semiconductor carbon nanotubes that are suspended over a dielectric trench, which is backed by a doped silicon substrate that acts as a gate. Alternating positive and negative differential resistance regions are generated as a function of the drain source values and can be slightly shifted by the gate voltage. Moreover, the negative differential resistance is retrieved in a large bandwidth, of up to 100 MHz, when the structure is excited with ac signals.