Abstract

The self-assembly of colloidal particles into the cubic diamond structure has been a longstanding goal because of its potential for making materials with a photonic band gap. These materials suppress the spontaneous emission of light and are valued for their applications as optical waveguides, filters, laser resonators, for improving light-harvesting technologies, and for other applications.  This talk will describe a method for making colloidal particles that self-assemble into the cubic colloidal diamond structure.  The particles consist of partially compressed tetrahedral clusters with retracted sticky patches.  They self-assemble via DNA-mediated patch-patch adhesion in coordination with a steric interlock mechanism that selects the proper staggered bond conformation required for cubic diamond. Simulations of the self-assembly process reveal a subtle interplay between the attractive patch-patch interactions, entropy, and gravity.