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Optical force field mapping in microdevices.

Gregor Knöner·Adrian Ratnapala·Timo A Nieminen·Chris J Vale·Norman R Heckenberg·Halina Rubinsztein-Dunlop
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Abstract

We present a method for characterizing microscopic optical force fields. Two dimensional vector force maps are generated by measuring the optical force applied to a probe particle for a grid of particle positions. The method is used to map out the force field created by the beam from a lensed fiber inside a liquid filled microdevice. We find transverse gradient forces and axial scattering forces on the order of 2 pN per 10 mW laser power which are constant over a considerable axial range (>35 microm). These findings suggest future useful applications of lensed fibers for particle guiding/sorting. The propulsion of a small particle at a constant velocity of 200 microm s(-1) is shown.

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LasersMicroscopy, Electron, ScanningOptics and PhotonicsSensitivity and SpecificityJournal Article

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Gregor Knöner, Adrian Ratnapala, Timo A Nieminen, Chris J Vale, Norman R Heckenberg, Halina Rubinsztein-Dunlop. 2006-09-22. Optical force field mapping in microdevices.. https://doi.org/10.1039/b608669a

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