Nonlinear optical nanomaterials in integrated photonic devices

Abstract

A frequency comb consists of a broad span of highly resolved and precisely spaced spectral lines. These lines are a tool that has been utilized in a wide range of applications requiring high-precision measurements, including atomic clocks, astronomic spectrographs, and spectroscopy. The phenomena responsible for frequency comb generation are based on nonlinear optical effects. However, these phenomena have required the comb generators to be extremely bulky, complex, and power-intensive. Micron-scale whispering gallery mode resonant cavities are an ideal candidate to overcome these limitations, as they are capable of achieving large power buildups within a small footprint. One strategy to further improve frequency comb generation in these resonators is to utilize nanomaterials coatings to enhance nonlinear optical phenomena. ? In this dissertation, various nanomaterial-based strategies are investigated for enhancing different nonlinear optical effects with the aim of improving frequency combs. First, fluoride nanoparticles coated on the surface of silica resonators are shown to improve the span of frequency combs by favorably altering material dispersion. Next, a plasmonic enhancement strategy based on gold nanorods and nonlinear optical polymers is demonstrated, yielding lower thresholds for frequency comb generation. Finally, a flexible fluorescent nanocomposite material is developed using zinc oxide nanomaterials. This work lays the foundation for future work that will utilize other nanomaterials and strategies for generating frequency combs in integrated photonic devices.