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arXiv · 1503.06815

Observation of decoherence in a carbon nanotube mechanical resonator

Ben H. Schneider·Vibhor Singh·Warner J. Venstra·Harold B. Meerwaldt·Gary A. Steele
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Abstract

In physical systems, decoherence can arise from both dissipative and dephasing processes. In mechanical resonators, the driven frequency response measures a combination of both, while time domain techniques such as ringdown measurements can separate the two. Here, we report the first observation of the mechanical ringdown of a carbon nanotube mechanical resonator. Comparing the mechanical quality factor obtained from frequency- and time-domain measurements, we find a spectral quality factor four times smaller than that measured in ringdown, demonstrating dephasing-induced decoherence of the nanomechanical motion. This decoherence is seen to arise at high driving amplitudes, pointing to a non-linear dephasing mechanism. Our results highlight the importance of time-domain techniques for understanding dissipation in nano-mechanical resonators, and the relevance of decoherence mechanisms in nanotube mechanics.

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Ben H. Schneider, Vibhor Singh, Warner J. Venstra, Harold B. Meerwaldt, Gary A. Steele. 2015-03-26. Observation of decoherence in a carbon nanotube mechanical resonator. https://doi.org/10.1038/ncomms6819

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