RSC Publishing


Publishing

 

Cover image for Faraday Discussions, select for current issue

Faraday Discussions

Discussion summary and research papers, in physical chemistry, chemical physics and biophysical chemistry.



Purchasing an Individual Volume

Purchase a recent Faraday Discussion as an individual volume

Subscribers

Non-subscribers

Free access



Paper

Faraday Discuss., 2008, 137, 319 - 333, DOI: 10.1039/b703994h


Characterization of microparticles with driven optical tweezers

Tiffany A. Wood, G. Seth Roberts, Sarayoot Eaimkhong and Paul Bartlett


We discuss how actively-driven optical tweezers may be used to characterize Brownian microparticles. Two experiments are described in detail. We follow the thermal fluctuations of a charged particle in an oscillatory electric field and demonstrate that charges as low as a few elementary charges can be measured accurately and reproducibly. Secondly, we measure the orientational dynamics of a trapped rotating droplet and use circular polarimetry within optical tweezers to determine in situ birefringence.