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arXiv · 2105.12330

A computational tool to characterize particle tracking measurements in optical tweezers

Michael A. Taylor·Warwick P. Bowen
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Abstract

Here we present a computational tool for optical tweezers which calculates the particle tracking signal measured with a quadrant detector and the shot-noise limit to position resolution. The tool is a piece of Matlab code which functions within the freely available Optical Tweezers Toolbox. It allows the measurements performed in most optical tweezers experiments to be theoretically characterized in a fast and easy manner. The code supports particles with arbitrary size, any optical fields and any combination of objective and condenser, and performs a full vector calculation of the relevant fields. Example calculations are presented which show the tracking signals for different particles, and the shot noise limit to position sensitivity as a function of the effective condenser NA.

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Michael A. Taylor, Warwick P. Bowen. 2021-05-26. A computational tool to characterize particle tracking measurements in optical tweezers. https://doi.org/10.1088/2040-8978%2F15%2F8%2F085701

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