Angle-Resolved Mid-Infrared Spectroscopy of Gyroid Photonic Crystals

Author: Khabiboulline, Emil Timergalievich

Year: 2016

Degree: Senior thesis (Major)

Advisor: Unknown, Unknown

Committee Member: None, None

Option: Physics

DOI: 10.7907/4GR6-3646

Abstract

Gyroid photonic crystals, which can form photonic topological insulators, offer a rich diversity of physics for fundamental study, in addition to yielding useful applications. Understanding their band structure is crucial towards advancing both fronts. An angle-resolved spectroscopy apparatus is constructed to experimentally measure band structures. Operating at wavelengths from 7.7 to 11.1 μm, it is employed to study single and double-gyroid photonic crystals, constructed of amorphous silicon in 5 μm unit cells. Transmittance and reflectance act as indicators of density of states, and are collected as spectra over angles of incidence ranging from 17 to 30 degrees. Comparison to theory confirms interesting features, such as bandgaps. Further simulation guides the design of a crystal amenable to the first experimental measurement of Weyl points at mid-infrared wavelengths.