Share Email Print

Proceedings Paper

Statics and dynamics of colloidal particles on optical trap arrays
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

We examine the statics and dynamics of charged colloids interacting with periodic optical trap arrays. In particular we study the regime where more than one colloid is confined in each trap, creating effective dimer, trimer, and higher order states called colloidal molecular crystals. The n-mer states have an effective orientational degree of freedom which can be controlled with an external driving field. In general, the external field causes a polarization effect where the orientation of the n-mers aligns with the external field, similar to liquid crystal systems. Additionally, under a rotating external drive the n-mers can rotate with the drive. In some cases a series of structural transitions in the colloidal crystal states occur in the rotating field due to a competition between the ordering of the colloidal molecular crystals and the polarization effect which orients the n-mers in the direction of the drive. We also show that for some parameters, the n-mers continuously rotate with the drive without switching, that depinning transitions can occur where the colloids jump from well to well, and that there are a number of distinct dynamical transitions between the phases. Finally, we illustrate colloidal orderings at fillings of more than four colloids per trap, indicating that it is possible to create higher order colloidal crystal cluster phases.

Paper Details

Date Published: 20 August 2009
PDF: 12 pages
Proc. SPIE 7400, Optical Trapping and Optical Micromanipulation VI, 74000J (20 August 2009); doi: 10.1117/12.824902
Show Author Affiliations
C. Reichhardt, Los Alamos National Lab. (United States)
C. J. Olson Reichhardt, Los Alamos National Lab. (United States)

Published in SPIE Proceedings Vol. 7400:
Optical Trapping and Optical Micromanipulation VI
Kishan Dholakia; Gabriel C. Spalding, Editor(s)

© SPIE. Terms of Use
Back to Top