Sensitivity enhancement of a whispering-gallery-mode microsphere resonance-shift sensor by coating of a high-refractive index (RI) layer is examined for TM polarization. The enhancement of sensitivity in response to particle adsorption or a RI change of the surroundings at the optimized layer thickness is greater for the TM mode compared with the TE mode, but the TM mode requires a thicker layer. A particular choice of the layer thickness allows the TE and TM shifts to match. Matching of the resonance frequency of the two modes is also examined.
|Original language||English (US)|
|Number of pages||7|
|Journal||Journal of the Optical Society of America B: Optical Physics|
|State||Published - Mar 2007|
ASJC Scopus subject areas
- Statistical and Nonlinear Physics
- Atomic and Molecular Physics, and Optics