Wednesday August 18, 2004
1:30 PM
PHO 339
| "Dielectric and semiconductor microspheres and silica optical fibers for optoelectronic applications"
Prof. Ali Serpengüzel
Koç University Because of their unique photophysical properties, dielectric microspheres have enjoyed increased attention in recent years. Morphology dependent resonances (MDR's) of microspheres can provide the necessary optical feedback for applications in spectroscopy, laser science and optical communications. In this work, MDR's of glass, sapphire, and silicon microspheres are excited by a tunable distributed feedback (DFB) laser, and the elastically scattered signal as well as the transmitted signal are detected. Efficient coupling to MDR's is achieved by using an optical fiber half coupler (OFHC). Resonance peaks in the elastic scattering spectra and associated dips in the transmission spectra are observed experimentally, and calculated theoretically. Detection of MDR's, by using a large area silicon photodiode in proximity to the microsphere-optical fiber half coupler (OFHC) is achieved. This coupling geometry heralds the possibility of compact optoelectronic channel dropping filters. |
