Few-hundred GHz Carbon Nanotube NEMS

J. O. Island; V. Tayari; A. C. McRae; A. R. Champagne

doi:10.1021/nl3018065

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arXiv · 1208.2709

Few-hundred GHz Carbon Nanotube NEMS

J. O. Island·V. Tayari·A. C. McRae·A. R. Champagne

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Abstract

We study 23 to 30 nm long suspended single-wall carbon nanotube quantum dots and observe both their stretching and bending vibrational modes. We use low-temperature DC electron transport to excite and measure the tubes' bending mode by making use of a positive feedback mechanism between their vibrations and the tunneling electrons. In these nano-electro-mechanical-systems (NEMS), we measure fundamental bending frequencies $f_{bend}\approx$ 75 - 280 GHz, and extract quality factors $Q \sim 10^{6}$. The NEMS' frequencies can be tuned by a factor of two with tension induced by mechanical breakjunctions actuated by an electrostatic force, or tension from bent suspended electrodes.

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J. O. Island, V. Tayari, A. C. McRae, A. R. Champagne. 2012-08-13. Few-hundred GHz Carbon Nanotube NEMS. https://doi.org/10.1021/nl3018065

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