title: Emission of Au nanoparticles with and without rhodamine 6G dye.
abstract: We have observed Stokes and anti-Stokes emission of Au nanoparticles suspended in methanol and rhodamine 6G dye solution. Photoluminescence of Au nanoparticles is a three-step process involving single-photon or three-photon excitation of electron-hole pairs, relaxation of excited electrons and holes, and emission from electron-hole recombination, possibly enhanced by surface plasmons. In the presence of dye, the excitation of anti-Stokes emission of gold involves two-photon absorption in rhodamine 6G molecules followed by the energy transfer to Au nanoparticles with simultaneous absorption of one pumping photon by Au. This mechanism significantly enhances anti-Stokes emission of gold nanoparticles in the presence of dye.
authors.affiliation: Center for Materials Research, Norfolk State University, Norfolk, Virginia 23504, USA.
authors.forename: G
authors.initials: G
authors.lastname: Zhu
authors.forename: V I
authors.initials: VI
authors.lastname: Gavrilenko
authors.forename: M A
authors.initials: MA
authors.lastname: Noginov