Optical Fiber Whispering Gallery Modes Resonances: Applications

The properties of whispering gallery modes (WGM) resonances of an optical fiber can be exploited in a number of different applications. Making these resonances tunable is essential for many applications. Using erbium-doped fibers to prepare the microresonator (MR), WGM resonances can be tuned by pumping the MR with an auxiliary diode laser, enabling an all-optical fine tuning of the resonances. The same idea can be exploited the other way round, an accurate measurement of pump-induced temperature variations in doped fibers can be achieved by monitoring the WGM resonances of a doped fiber when being used. In addition, a tunable narrow linewidth fiber lasers is demonstrated using a tunable MR prepared with a slightly tapered fiber.