Optical modulators for integrated photonic systems

Optical components and systems manufactured with semiconductor wafer processing technologies have the potential to dramatically reduce the cost of photonics. This dissertation will present research results into two such chip-scale optics technologies that have the potential to revolutionize the way in which data is transmitted and manipulated. The semiconductor microresonator modulators and photonic crystal modulators discussed in this work are over an order of magnitude smaller than currently available modulators and can be made in semiconductor materials with standard processing techniques developed for the microelectronics industry.; In addition to presenting these two modulator technologies, this dissertation will report on the optical phase characteristics of microdisk resonators with different ratios between the coupling loss to the waveguide and the internal loss in the microdisks. By controlling the ratio of these loss mechanisms to each other, the optical phase of a signal transmitted through the waveguide coupled microdisk system can be controlled.; Photonic bandgap technology is an attractive research direction because it enables the confinement of light inside an optical material to a dimension that is roughly equal to the optical wavelength in that material. One and two dimensionally periodic photonic crystal structures are discussed including distributed Bragg reflectors (1D) and photonic crystal waveguides (2D). Both rely on a periodically varying index of refraction to form optical frequency bandgaps in which light is not allowed to propagate through the material. The optical phase from reflection off of a DBR mirror is experimentally demonstrated with a DBR mirror in a free space Mach-Zehnder interferometer. Two dimensionally periodic photonic crystals are used to construct waveguides and couplers in this work. The propagation loss in these demonstrated structures has been reduced to the point where this technology is attractive for chip-scale integrated optics. Directional couplers functioning as power splitters, wavelength filters, and modulators are presented as well.