Colloidal Assembly of Photonic Band Gap Coatings

University Of Minnesota-Twin Cities, Minneapolis MN

Investigators

Abstract

CTS-0332484 D. Norris, U of Minnesota This proposal aims to determine the mechanisms by which planar opals (i.e., crystalline layers of monodisperse submicron silica spheres) grow on substrates that are immersed in colloidal suspensions. Recent work has shown that such planar opals can provide a simple route to form photonic band gap materials. As photonic band gap structures can provide a novel material for controlling light, simple approaches to these materials are desired. However, the mechanism by which planar opals form is not understood. The proposed research will simultaneously pursue an experimental and theoretical investigation of planar opal growth. In experiment the team will use optical microscopy to visualize the growth of planar opals in real time with sufficient resolution to observe the motion of individual colloidal spheres. Theoretically, the team will examine the role of solvent flow through the pore space of close-packed spheres in the formation of planar opals. One graduate student, who is co-advised by the two PIs will be involved in both aspects of the project. The graduate student will be joined in experiment by an undergraduate student. The expected intellectual impact of this project is an enhanced ability to fabricate photonic materials and understand their properties. The project will also: provide a multidisciplinary environment to educate graduate students in the technologically important area of photonics; provide mentorship and an enhanced research experience for undergraduate students; and develop connections between academic and industrial researchers involved in both photonics and coatings technologies.