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High quality factor mechanical resonance in a silicon nanowire

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 نشر من قبل Sergey Kafanov
 تاريخ النشر 2018
  مجال البحث فيزياء
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Resonance properties of nanomechanical resonators based on doubly clamped silicon nanowires, fabricated from silicon-on-insulator and coated with a thin layer of aluminum, were experimentally investigated. Resonance frequencies of the fundamental mode were measured at a temperature of $20,mathrm{mK}$ for nanowires of various sizes using the magnetomotive scheme. The measured values of the resonance frequency agree with the estimates obtained from the Euler-Bernoulli theory. The measured internal quality factor of the $5,mathrm{mu m}$-long resonator, $3.62times10^4$, exceeds the corresponding values of similar resonators investigated at higher temperatures. The structures presented can be used as mass sensors with an expected sensitivity $sim 6 times 10^{-20},mathrm{g},mathrm{Hz}^{-1/2}$.



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