Escape from an optoelectronic tweezer trap: experimental results and simulations

Zhang, S. et al. (2018) Escape from an optoelectronic tweezer trap: experimental results and simulations. Optics Express, 26(5), pp. 5300-5309. (doi: 10.1364/OE.26.005300)

Abstract

Optoelectronic tweezers (OET) are a microsystem actuation technology capable of moving microparticles at mm s−1 velocities with nN forces. In this work, we analyze the behavior of particles manipulated by negative dielectrophoresis (DEP) forces in an OET trap. A user-friendly computer interface was developed to generate a circular rotating light pattern to control the movement of the particles, allowing their force profiles to be conveniently measured. Three-dimensional simulations were carried out to clarify the experimental results, and the DEP forces acting on the particles were simulated by integrating the Maxwell stress tensor. The simulations matched the experimental results and enabled the determination of a new “hopping” mechanism for particle-escape from the trap. As indicated by the simulations, there exists a vertical DEP force at the edge of the light pattern that pushes up particles to a region with a smaller horizontal DEP force. We propose that this phenomenon will be important to consider for the design of OET micromanipulation experiments for a wide range of applications.

• Item Type: Articles
• Additional Information: Natural Sciences and Engineering Research Council of Canada (NSERC) (RGPIN 2014-06042, CREATE 482073-16); National Natural Science Foundation of China (NSFC) (51403244, 61323001, 11690031, 61490715, 11304401); Natural Science Foundation of Guangdong Province (2014A030313104); State Key Laboratory of Optoelectronic Materials and Technologies (OEMT), Sun Yat-sen University (SYSU) (Open Project: OEMT-2017-KF-03).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Neale, Professor Steven
• Authors: Zhang, S., Nikitina, A., Chen, Y., Zhang, Y., Liu, L., Flood, A. G., Juvert, J., Chamberlain, M. D., Kherani, N. P., Neale, S. L., and Wheeler, A. R.
• College/School: College of Science and Engineering > School of Engineering > Systems Power and Energy
• Journal Name: Optics Express
• Publisher: Optical Society of America
• ISSN: 1094-4087
• ISSN (Online): 1094-4087
• Published Online: 21 February 2018
• Copyright Holders: Copyright © 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
• First Published: First published in Optics Express 26(5):5300-5309
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher