Microsphere integration in active and passive photonics devices

As important step towards integration of microspheres in compact functional photonics devices, we demonstrate direct efficient coupling of light in and out of high-Q whispering-gallery (WG) modes in silica microspheres using angle-polished single mode fibers. Based on this principle, we present a 1-inch fiber-pigtailed microsphere module that can be used for fiberoptic applications, and a fiber-coupled erbium-doped microsphere laser at 1.55 mu m. In addition, we report preliminary data on the intensity modulation based on high-Q WG modes in a lithium niobate sphere. We also demonstrate a novel geometry WG-mode optical microcavity that combines Q similar to 10(7), typical for microspheres, with few-nanometer mode spacing earlier available in lower quality factor Q similar to 10(4) microfabricated planar rings.