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arXiv · 1803.03865

Charge sensitivity enhancement via mechanical oscillation in suspended carbon nanotube devices

Pasi Häkkinen·Andreas Isacsson·Alexander Savin·Jaakko Sulkko·Pertti Hakonen
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Abstract

Single electron transistors (SETs) fabricated from single-walled carbon nanotubes (SWNTs) can be operated as highly sensitive charge detectors reaching sensitivity levels comparable to metallic radio frequency SETs (rf-SETs). Here we demonstrate how the charge sensitivity of the device can be improved by using the mechanical oscillations of a single-walled carbon nanotube quantum dot. To optimize the charge sensitivity $δQ$, we drive the mechanical resonator far into the nonlinear regime and bias it to an operating point where the mechanical third order nonlinearity is cancelled out. This way we enhance $δQ$, from 6 $μe/\sqrt{\textrm{Hz}}$ for the static case, to 0.97 $μe/\sqrt{\textrm{Hz}}$, at a probe frequency of $\sim$ 1.3 kHz.

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Pasi Häkkinen, Andreas Isacsson, Alexander Savin, Jaakko Sulkko, Pertti Hakonen. 2018-03-10. Charge sensitivity enhancement via mechanical oscillation in suspended carbon nanotube devices. https://doi.org/10.1021/nl504282s

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