Intrinsic fluorescence from individual silver nanoparticles

Optical microscopy and spectroscopy on individual silver nanoparticles reveals strong emission for blue laser excitation. The silver nanoparticles (View the MathML source in size) are spin-coated on glass. The emitted light shows blinking and spectral fluctuations under continuous excitation. Identical spectral behaviour was observed on oxidised silver powder indicating that the emissive sites are small silver clusters (few atoms) photo-activated by light illumination of the oxide.