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arXiv · 1311.2217

Microrheology measurements with a hanging-fiber AFM probe

Clemence Devailly·Justine Laurent·Audrey Steinberger·Ludovic Bellon·Sergio Ciliberto
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Abstract

A method to measure the viscosity of liquids at microscales is presented. It uses a thin glass fiber fixed on the tip of the cantilever of an extremely low noise Atomic Force Microscope (AFM), which accurately measures the cantilever {deflection}. When the fiber is dipped into the liquid the dissipation of the cantilever-fiber system increases. This dissipation, linked to the liquid viscosity, is computed from the power spectral density of the thermal fluctuations of the cantilever {deflection}. The {high sensitivity of the AFM} allows us to show the existence and to develop a model of the coupling between the dynamics of the fiber and that of the cantilever. This model {accurately} fits the experimental data. The advantages and draw-backs of the method are discussed

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Clemence Devailly, Justine Laurent, Audrey Steinberger, Ludovic Bellon, Sergio Ciliberto. 2013-11-09. Microrheology measurements with a hanging-fiber AFM probe. https://arxiv.org/abs/1311.2217

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