Optically Induced Rapid Electrokinetic Patterning: A Study of the Operational Regimes and Dominant Forces

We study a recently proposed optically induced electrokinetic colloidal particle patterning technique that can pattern/translate or trap particle clusters on an electrode surface using high power laser beams and under an applied AC field. By exploring variations in particle density, with changes in various factors, using Voronoi tessellations we show that the role of various forces changes dramatically with conductivity. For low conductivity (∼2 mS/m) solutions we show that particle density increases with frequency primarily due to a lowering of the induced dipole moment of the particle.