Microsphere resonator integrated inside a microstructured optical fiber

Optics Letters (Impact Factor: 3.29). 04/2013; 38(8):1301-3. DOI: 10.1364/OL.38.001301
Source: PubMed


A compact and robust scheme for broadband excitation of whispering gallery mode (WGM) resonances into a microsphere is demonstrated. A polymer microsphere (10 μm) is encapsulated into the capillary of a microstructured optical fiber, in direct contact with the guiding core. Such a configuration allows efficient and reproducible excitation of the in-MOF-microsphere resonator that is characterized by two launch/collection schemes: core input/scattering output, and sphere input/core output. The latter allows an excitation of the microsphere WGMs externally to the fiber. Numerically calculated WGM spectra are in agreement with experiments. Q factors in the range of 103 are typically measured.

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Available from: Gianluigi Zito, Mar 04, 2015
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    • "Similar measurements were performed with the same microsphere samples in aqueous solution, drastically decreasing the refractive index contrast between the microresonator and its surrounding environment, resulting in higher confinement losses of the propagating modes as the reflectivity at the interface is reduced and a higher portion of the evanescent field leaks out of the resonator. As a consequence, all the higher order modes are quenched and only the first order TE and TM modes can be seen in Figure 4 (A), which shows a typical WGM spectrum of a 10 μm dye doped polystyrene microsphere in water [22] [23] . Figure 4 "
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