Dr. Ivan Smalyukh, University of Colorado, Boulder
Tunable composite materials with novel physical behavior can be designed through integrating unique optical properties of solid nanostructures with the facile responses of soft matter to weak external stimuli, but this approach remains challenged by their poorly controlled co-assembly at the mesoscale. Using scalable wet chemical synthesis procedures, we fabricated anisotropic photon-upconverting, plasmonic, and gold-silica-dye colloidal nanostructures and then organized them into the device-scale electrically tunable composites by simultaneously invoking molecular and colloidal self-assembly [1-4]. We show that the ensuing ordered colloidal dispersions of shape-anisotropic nanostructures exhibit tunable properties, such as the fluorescence decay rates and emission intensity. We characterize how these properties depend on low-voltage fields and polarization of both the excitation and emission light, demonstrating a great potential for the practical realization of an interesting breed of nanostructured photonic composites.  H. Mundoor, B. Senyuk, and I. I. Smalyukh. Science 352, 69-73 (2016).  L. Jiang, H. Mundoor, Q. Liu, and I. I. Smalyukh. ACS nano 10, 7064-7072 (2016)  Y. Zhang, Q. Liu, H. Mundoor, Y. Yuan, I. I. Smalyukh. ACS Nano 9, 3097-3108 (2015).  H. Mundoor and I. I. Smalyukh. Small 11, 5572–5580 (2015).