Mixing at 50 GHz using a single-walled carbon nanotube transistor

We have probed the electrical properties of top-gated single-walled carbon nanotube transistors at frequencies up to 50 GHz by using the device as a microwave mixer. We find that the amplitude of the mixing signal decays as a function of frequency with a characteristic time constant that is limited by the setup. Despite the setup-limited cutoff frequency of similar to 10 GHz, we show that the devices still operate faster than 50 GHz. (C) 2005 American Institute of Physics.