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arXiv · 2402.04887

Multimode characterization of an optical beam deflection setup

Alex Fontana·Ludovic Bellon
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Abstract

Optical beam deflection is a popular method to measure the deformation of micromechanical devices. As it measures mostly a local slope, its sensitivity depends on the location and size of the optical spot. We present a method to evaluate precisely these parameters, using the relative amplitude of the thermal noise induced vibrations. With a case study of a microcantilever, we demonstrate the accuracy of the approach, as well as its ability to fully characterize the sensitivity of the detector and the parameters (mass, stiffness) of the resonator.

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Alex Fontana, Ludovic Bellon. 2024-02-07. Multimode characterization of an optical beam deflection setup. https://doi.org/10.1103/physrevapplied.22.014044

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