title: Nonlinear correlation spectroscopy (NLCS).
abstract: We present a novel concept for optical spectroscopy called nonlinear correlation spectroscopy (NLCS). NLCS analyses coherent field fluctuations of the second and third harmonic light generated by diffusing nanoparticles. Particles based on noncentrosymmetric nonlinear materials such as KNbO(3) show a strong second as well as third harmonic response. The method and the theory are introduced and experimental NLCS results in fetal calf serum are presented showing the promising selectivity of this technique for measurement in complex biological environments.
authors.affiliation: Laboratoire d'Optique Biomédicale LOB, École Polytechnique Fédérale de Lausanne (EPFL), Switzerland. matthias.geissbuehler@epfl.ch
authors.forename: Matthias
authors.initials: M
authors.lastname: Geissbuehler
authors.forename: Luigi
authors.initials: L
authors.lastname: Bonacina
authors.forename: Vladislav
authors.initials: V
authors.lastname: Shcheslavskiy
authors.forename: Noelia L
authors.initials: NL
authors.lastname: Bocchio
authors.forename: Stefan
authors.initials: S
authors.lastname: Geissbuehler
authors.forename: Marcel
authors.initials: M
authors.lastname: Leutenegger
authors.forename: Iwan
authors.initials: I
authors.lastname: Märki
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Wolf
authors.forename: Theo
authors.initials: T
authors.lastname: Lasser
mesh_terms: D000818:Animals; D002417:Cattle; D008027:Light; D049329:Nanostructures / Q000737:chemistry*; D017711:Nonlinear Dynamics; D010316:Particle Size; D012542:Scattering, Radiation; D044967:Serum / Q000737:chemistry*; D013057:Spectrum Analysis / Q000379:methods*