Tip-enhanced Rayleigh scattering and photoluminescence from semiconductor nanoparticles

Tip-enhanced Rayleigh scattering images of Ge quantum dots grown on Si substrate have been observed. Changing the wavelength of the incidence light, the contrast of the images is reversed. It is found that the scattering intensity depends strongly on dielectric constants of materials under the probe. Tip-enhanced photoluminescence of In_0.3Ga_0.7N films has also been reported. The strong local enhancement of the photoluminescence of the localized excitons has been observed in the vicinity of a silver nano-particle attached to the end of the probe.