Microstructured interfaces for generation of structural coloration via total internal reflection

Lauren Zarzar, Assistant Professor
Department of Chemistry, Pennsylvania State University

A variety of physical phenomena create color, such as optical absorption by pigments, optical dispersion, and structural color by the interference of light. I will describe a previously unrecognized mechanism for creating iridescent structural color with large angular spectral separation by taking advantage of total internal reflections within concave microstructures. The effect is readily observed in systems as simple as water drops condensed on a transparent substrate, as well as in more complex materials, including multiphase droplets, 3D patterned polymer surfaces, and solid micro-particles. Such design principles and predictive theory outlined here will be of interest for fundamental exploration in optics and application in functional colloidal inks and paints, displays, and sensors.

About the Speaker

Lauren is currently an assistant professor in the Department of Chemistry at The Pennsylvania State University. As an undergraduate, Lauren attended the University of Pennsylvania, earning bachelor’s degrees in Chemistry (from the College of Arts and Sciences) and Economics (from Wharton). Subsequently, she attended graduate school at Harvard University in the Department of Chemistry and Chemical Biology, and received both the NSF Graduate Research Fellowship and the NDSEG Fellowship. Her graduate work focused on the development and study of bio-inspired, chemo-mechanical actuation systems in which stimuli-responsive hydrogel drives the controlled movement of surface-attached, high-aspect-ratio polymeric microstructures. During the summers of graduate school, Lauren worked at the Advanced Materials Laboratory of Sandia National Laboratories, investigating multiphoton patterning of responsive gels and nanocrystalline metals. As a postdoctoral associate at MIT, she developed complex multiphase emulsions that are dynamically reconfigurable and responsive to external stimuli. Currently, her research group at Penn State focuses on dynamic materials, spanning complex fluids to polymers, and the laser direct writing of diverse materials at liquid-solid interfaces. She is the recipient of the 3M Non-Tenured Faculty Award, an ARO Young Investigator Program grant, and the Army – Early Career Award for Scientists and Engineers (ECASE) award.