Abstract-We present quantitative predictions of the performance of nanotubes and nanowires as antennas, including the radiation resistance, the input reactance and resistance, and antenna efficiency, as a function of frequency and nanotube length. Particular attention is paid to the quantum capacitance and kinetic inductance. In so doing, we also develop a circuit model for a transmission line made of two parallel nanotubes, which has applications for nano-interconnect technology.

Centimeter scale aligned carbon nanotube arrays are grown from nanoparticle/metal catalyst pads. We find the nanotubes grow both with and "against the wind". A metal underlayer provides in-situ electrical contact to these long nanotubes with no post growth processing needed. Using the electrically contacted nanotubes, we study electrical transport of 0.4 cm long nanotubes. The source drain I-V curves are quantitatively described by a classical, diffusive model. Our measurements show that the outstanding transport properties of nanotubes can be extended to the cm scale and open the door to large scale integrated nanotube circuits with macroscopic dimensions.

We present the first demonstration of single-walled carbon nanotube transistor operation at microwave frequencies. To measure the sourcedrain ac current and voltage at microwave frequencies, we construct a resonant LC impedance-matching circuit at 2.6 GHz. Both semiconducting and metallic nanotubes are measured. Varying the back-gate voltage for a semiconducting nanotube at dc varies the 2.6-GHz source-drain impedance. In contrast, varying the back-gate voltage on a metallic nanotube at dc has no effect on the microwave source-drain impedance. We find the ac source-drain impedance to be different than the dc source-drain resistance, which may be due to the distributed nature of the capacitive and inductive impedance of the contacts to the nanotube.

No abstract

Dielectrophoresis is an electronic analogue1,2 of optical tweezers3 based on the same physical principle: an ac electric field induces a dipole moment on an object in solution, which then experiences a force proportional to the gradient of the field intensity. For both types of tweezers, this force must compete with thermal Brownian4 motion to be effective, which becomes increasingly difficult as the particle size approaches the nanometer scale. Here we show that this restriction can be overcome by using the large electric field gradient in the vicinity of a carbon nanotube to electronically manipulate nanoparticles down to 2 nm in diameter.