Abstract

Liquid microdroplet resonators provide an excellent tool for optical studies due to their innate smoothness and high quality factors, but they can be difficult to control. By using 3D printed mounts to support the droplets, we can obtain precise control over the droplet geometries and positions. We here present our work with oil, water, and ice microdroplets, as well as tools required to enable their study. We first present methods for creating 3D printed mounts for oil microdroplet resonators. The mounts enable precise positioning of the droplets relative to a tapered optical fiber. The oil microdroplet resonators exhibited quality factors of over 4 × 10^5. Water microdroplet resonators are more difficult to create due to the evaporation of water. By supporting the droplet on a 3D printed structure that supplies water to the droplet, we can maintain a water microdroplet resonator in an ambient environment while also controlling its shape and size. The resulting resonators have high quality factors, with values measured as high as 6 × 10^8. Ice microdroplets may be useful as optical resonators; however, typically ice appears cloudy due to trapped air bubbles. We present a method for freezing clear ice microdroplets in both humid and dry environments, enabling the formation of a clear ice droplet without the risk of additional crystal growth. To facilitate the freezing of droplets in a low-humidity environment, we have developed an environmental control chamber capable of maintaining an arbitrary humidity level and controlling the temperature of a small sample. We here present instructions for its manufacture as well as validation of its function. Finally, we present an automated fabrication system for the creation of tapered and dimpled optical fibers. Tapered fibers have been essential in our work as tools for optical coupling to microdroplet resonators, and dimpled fibers allow for coupling to on-chip structures. The system we present allows for their fabrication with no user input and is able to produce fibers with efficiencies over 90% at a high yield.

Degree

PhD

College and Department

Ira A. Fulton College of Engineering; Electrical and Computer Engineering

Rights

https://lib.byu.edu/about/copyright/