RUI: Chemical Approaches to the Fabrication of Photonic Crystals of Non-Linear Optical Materials

Spelman College, Atlanta GA

Investigators

Abstract

The Advanced Materials Program in the Chemistry Division makes this RUI award to Spelman College to fabricate photonic bandgap crystals of ZnGeP2 that exhibit substantial birefringence, and thus will have well-established applications in the form of conventional phase-matched NLO devices. With this award, Professor McCall will be using following approaches to study the photonic bandgap crystals: 1) optimize liquid phase epitaxy of ZnSiP2-ZnGeP2/GaP heterostructures, guided by theoretical modeling and simulations of homogeneous chemical kinetics, coupled to convective and diffusive transport of reactive precursors to surface reactions that feed epitaxial growth; 2) fabricate ZnSiP2-ZnGeP2/GaP photonic bandgap crystals by selective chemical soft solution machining and digital vapor etching, including electrochemical and photochemical approaches, and to develop the theoretical basis for the understanding of these fabrication processes; and 3) study the structural, electrical and optical properties of ZnSiP2-ZnGeP2 photonic bandgap crystals with optimum interfacial refractive index offsets of the fabricated materials. With this award, photonic bandgap crystals will be fabricated, and their structural, electrical and optical properties will be determined including theoretical modeling and simulations. These crystals would be useful for the integration of NLO waveguides and tunable sources of coherent infrared radiation into compact and robust systems for the detection and classification of infrared spectroscopic signatures of chemical and biochemical agents. The proposed studies will provide undergraduate students with comprehensive hands on experience in research, supplemented by computational solutions to problems of physical chemistry and materials science with practical applications. In addition, the project has the potential to attract more under-represented minority students to careers in science.