Date of Graduation
Statler College of Engineering and Mineral Resources
Lane Department of Computer Science and Electrical Engineering
Jeremy M Dawson
Nanophotonics, specifically photonic crystals (PhCs), offer unique optical bandgap engineering possibilities that has driven the emergence of a variety of device platforms, including: beam splitters, nano-cavity resonators, lasers, fibers, waveguides and highly sensitive optofluidic biosensor devices. The design and fabrication of accurate lattice parameters for a PhC is very important to achieving the desired operating bandgap. The inclusion of tunability in thin film PhCs not only offers a means of adjusting for fabrication errors but also a mechanism to increase device functionality as well as providing a wider range of operating wavelengths. Nitride thin films, specifically Aluminum Nitride (AlN) and Gallium Nitride (GaN), are being used as PhC slab materials by our group due to their desirable optical properties at visible wavelengths and high chemical and thermal stability under harsh conditions. The inherent piezoelectric properties of these materials offer a means of direct tuning of PhC lattice parameters through piezoelectric deformation.;This thesis presents the results of research aimed at actively tuning the bandgap of PhCs fabricated in piezoelectric AlN thin films. Theoretical investigations of the bandgap tuning of =as-drawn' and deformed 1- and 2-D PhC lattice structures using coupled results from PhC optical behavioral modeling and finite element mechanical simulations are discussed. The results of experimental characterization of the optical and mechanical (i.e. tuning) properties of micro to nanoscale PhC lattice structures fabricated in Si and AlN using e-beam and optical lithography and reactive ion etching are presented. Experimental data is then used to explore the bandwidth tuning capability of large-area periodic nanophotonic structures.
Yalamanchili, Hyma, "Dynamic bandgap tuning of solid thin film photonic crystal structures" (2010). Graduate Theses, Dissertations, and Problem Reports. 4677.