To date investigations of the dynamics of driven colloidal systems have focused on hydrodynamic interactions and often employ optical (laser) tweezers for manipulation. However, the optical fields that provide confinement and drive also result in electrodynamic interactions that are generally neglected. We address this issue with a detailed study of 150-nm Ag nanoparticles electrodynamically interacting in an optical ring vortex trap using 150-nm diameter Ag nanoparticles. We term the resultant electrodynamically interacting nanoparticles a driven optical matter system. First, the instrument used to create driven optical matter is described with special attention to optimizing the components that create the optical ring vortex. Next, we explore a systematic study of the electrodynamical interactions of driven optical matter using experimental and simulation methods We determined the nature of optical ring vortex gives rise to increased fluctuations of interparticle separation that should not be neglected in any optically driven colloidal system. Then, we use driven optical matter to test various kinetic models in a non-equilibrium barrier crossing experiment. We show that one can easily misinterpret dynamics from barrier crossing models through experiment and simulation where no barrier is present. Afterwards, barrier crossing in driven optical matter is explored in a system where the barrier is not fixed at one location but moves with the particles. This “particle passing” process also involves a 2-dimensional reaction coordinate that modulates as a pair of particles is driven around the optical ring vortex. Finally, localization errors that result from particle tracking are explored and a new method for correcting those errors, the SPIFF algorithm, is presented. Supplemental material for this dissertation includes software to control a spatial light modulator and analysis of driven optical matter experiments.




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