title: Light-induced changes of the refractive indices in a colloid of gold nanoparticles in a nematic liquid crystal.
abstract: It was shown that irradiation of a nematic liquid crystal doped with metal nanoparticles in the visible near the plasmon resonance band led to strong thermal changes of the refractive indices. The effect was studied by recording of dynamic optical gratings in the colloid. Nanoparticles "worked" as effective nano-heaters in a matrix causing the order parameter decrease around the particles. A large nonlinearity parameter (n (2) ≈ 10(-2) cm(2)/kW and fast response (≈ 0.7 ms), with no detectable particles' aggregation and excellent photo- thermo-stability make these colloids potentially attractive nonlinear optical media. Application of a dynamic holography technique allowed measuring the coefficients of thermal conductivity of the liquid crystal along the director k (||) = (0.4 ± 0.02) W m(-1)K(-1) and perpendicular to the director k (⊥) = (0.2 ± 0.01) W m(-1)K(-1).
authors.affiliation: Institute of Physics, National Academy of Sciences of Ukraine, Pr. Nauki 46, 03028 Kyiv, Ukraine.
authors.forename: D
authors.initials: D
authors.lastname: Lysenko
authors.forename: E
authors.initials: E
authors.lastname: Ouskova
authors.forename: S
authors.initials: S
authors.lastname: Ksondzyk
authors.forename: V
authors.initials: V
authors.lastname: Reshetnyak
authors.forename: L
authors.initials: L
authors.lastname: Cseh
authors.forename: G H
authors.initials: GH
authors.lastname: Mehl
authors.forename: Y
authors.initials: Y
authors.lastname: Reznikov