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arXiv · 1805.08101

Calibrating torsional eigenmodes of micro cantilevers for dynamic measurement of frictional forces

Per-Anders Thorén·Riccardo Borgani·Daniel Forchheimer·David B. Haviland
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Abstract

Non-invasive thermal noise calibration of both torsional and flexural eigenmodes is performed on numerous cantilevers of 10 different types. We show that for all tipless and short-tipped cantilevers, the ratio of torsional to flexural mode stiffness is given by a constant, times the ratio of their resonant frequencies. By determining this constant we enable a calibration of the torsional eigenmode, starting from a calibration of the flexural eigenmode. Our results are well motivated from beam theory and we verify them with finite element simulation.

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Per-Anders Thorén, Riccardo Borgani, Daniel Forchheimer, David B. Haviland. 2018-05-21. Calibrating torsional eigenmodes of micro cantilevers for dynamic measurement of frictional forces. https://doi.org/10.1063/1.5038967

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