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A new capacitive sensor for displacement measurement in a surface force apparatus

F. Restagno·J. Crassous·E. Charlaix·M. Monchanin
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Abstract

We present a new capacitive sensor for displacement measurement in a Surface Forces Apparatus (SFA) which allows dynamical measurements in the range of 0-100 Hz. This sensor measures the relative displacement between two macroscopic opaque surfaces over periods of time ranging from milliseconds to in principle an indefinite period, at a very low price and down to atomic resolution. It consists of a plane capacitor, a high frequency oscillator, and a high sensitivity frequency to voltage conversion. We use this sensor to study the nanorheological properties of dodecane confined between glass surfaces.

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F. Restagno, J. Crassous, E. Charlaix, M. Monchanin. 2001-02-13. A new capacitive sensor for displacement measurement in a surface force apparatus. https://doi.org/10.1088/0957-0233%2F12%2F1%2F302

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