Figure 8.

WGMs in the fluorescence spectra of CdSe/ZnS cQDs coating ≃3 μm polystyrene microspheres. The spectra shown on the same scale are for two different microspheres. A small fluorescence background is observed as well as tiny peaks in each WGM. These peaks are attributed to polar modes, indicating that the spherical symmetry of the microspheres is broken

Charlebois et al. Nanoscale Research Letters 2010 5:524-532   doi:10.1007/s11671-010-9541-1