We are studying both the basic physics and device applications of dielectric whispering-gallery-mode (WGM) optical microresonators. One example of the microresonators under study is a sub-millimeter sphere of fused silica, made by melting the end of an optical fiber. In a WGM the light, trapped by total internal reflection, skims just under the sphere’s surface as it circulates around the sphere at its equator. Tunable laser light can be coupled into a WGM from a tapered optical fiber adjacent to the sphere in its equatorial plane.  More recently, we have been using hollow bottle resonators, made from silica capillaries etched to thin their walls, then heated and pressurized to form a bottle-shaped bulge.

 

Extremely low losses enable light in a WGM to make tens of thousands of round trips in the microresonator. In addition, the WGM’s evanescent components allow the light to interact with material in the ambient or on the resonator’s surfaces (outer and inner). Together, these two properties enable numerous applications. In addition to the fundamental optics of microresonators, our research topics include chemical and surface-effect sensing, classical analogs to quantum-optical phenomena, quantum-dot microlasers, measurement of thermal accommodation coefficients, evanescent coupling enhancement, and plasmonics. More specific information may be found by navigating around this website, in particular under Research and under Publications.