Random lasing from dye-gold nanoparticles in polymer films: Enhanced gain at the surface-plasmon-resonance wavelength

The authors report on gold nanoparticle enhancement of the gain in dyes/nanoparticles/polymer film for random lasers. Importantly, they demonstrate a lower threshold for lasing and a stronger output intensity, which depend on the nanoparticle (NP) size. By calculating the NP scattering resonance using Mie theory and the measured surface-plasmon resonance, we can qualitatively explain the results, suggesting that the random lasing properties are dominated by an enhanced photon scattering mechanism induced by the surface plasmons. (c) 2006 American Institute of Physics.