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arXiv · 1707.02926

Strong 4-mode coupling of nanomechanical string resonators

Katrin Gajo·Simon Schüz·Eva M. Weig
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Abstract

We investigate mechanical mode coupling between the four fundamental flexural modes of two doubly-clamped, high-Q silicon-nitride nanomechanical string resonators. Strong mechanical coupling between the strings is induced by the strain mediated via a shared clamping point, engineered to increase the exchange of oscillatory energy. One of the resonators is controlled dielectrically, which results in strong coupling between its out-of-plane and in-plane flexural modes. We show both, inter-string out-of-plane-in-plane and 3-mode resonance of the four coupled fundamental vibrational modes of a resonator pair, giving rise to a simple and a multimode avoided crossing, respectively.

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Katrin Gajo, Simon Schüz, Eva M. Weig. 2017-10-02. Strong 4-mode coupling of nanomechanical string resonators. https://doi.org/10.1063/1.4995230

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