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arXiv · 1006.0777

Sagnac Interferometer Enhanced Particle Tracking in Optical Tweezers

M. A. Taylor·J. Knittel·M. T. L. Hsu·H. -A. Bachor·W. P. Bowen
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Abstract

A setup is proposed to enhance tracking of very small particles, by using optical tweezers embedded within a Sagnac interferometer. The achievable signal-to-noise ratio is shown to be enhanced over that for a standard optical tweezers setup. The enhancement factor increases asymptotically as the interferometer visibility approaches 100%, but is capped at a maximum given by the ratio of the trapping field intensity to the detector saturation threshold. For an achievable visibility of 99%, the signal-to-noise ratio is enhanced by a factor of 200, and the minimum trackable particle size is 2.4 times smaller than without the interferometer.

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M. A. Taylor, J. Knittel, M. T. L. Hsu, H. -A. Bachor, W. P. Bowen. 2010-06-04. Sagnac Interferometer Enhanced Particle Tracking in Optical Tweezers. https://doi.org/10.1088/2040-8978%2F13%2F4%2F044014

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