Confocal laser imaging and annealing of quantum-dot-coated silica colloidal crystals

We demonstrate the ability to image, melt, and anneal repulsive electrostatic and attractive depletion colloidal crystals of quantum-dot-decorated SiO(2) microparticles (QDSs). QDS colloidal crystals showed increased thermal motion, melting, and convection only in the presence of CSLM imaging, which we attribute to quantum dot (QD) heating. We exploit this local heating effect to anneal a single defect-rich, polycrystalline domain. Our results demonstrate a method to anneal colloidal crystals locally with focused lasers and the role of heating when using many QD tags per particle in CSLM imaging.