Mode structure in the luminescence of Si-nc in cylindrical microcavities

We present photoluminescence studies of silicon-nanocrystal (Si-nc)-coated cylindrical microcavities. The particular geometries investigated include regular optical fibers with a Si-nc coating on the outside surface and hollow fibers where the coating is on the inner surface. The coatings were prepared using an inexpensive and straightforward solution-based process that yields a high-quality film, which can sustain high Q-factor whispering gallery modes. The combination of Si-ncs and optical microcavities with strong confinement has promising potential for applications like sensing, optical communications and may be a possible route toward a Si-nc laser.