title: Third-harmonic generation from single gold nanoparticles.
abstract: We report the first observation of third-harmonic signals from individual gold colloids down to 40 nm diameter. Excited with 1-ps pulses at 1500 nm, the colloids generate 500-nm light, close to the plasmon resonance. The third-harmonic intensity varies as the square of the colloid surface area. Although weak, the third-harmonic signals of gold labels as small as 15 nm in diameter are expected to be accessible with 100-fs pulses. They could be used in microscopy for single-biomolecule tracking.
authors.affiliation: MoNOS, Huygens Laboratory, Universiteit Leiden, P.O. Box 9504, 2300 RA Leiden, The Netherlands.
authors.forename: Markus
authors.initials: M
authors.lastname: Lippitz
authors.forename: Meindert A
authors.initials: MA
authors.lastname: van Dijk
authors.forename: Michel
authors.initials: M
authors.lastname: Orrit
mesh_terms: D017979:Gold Colloid / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*
chemical_list: D017979:Gold Colloid