Effect of lamellar nanostructures on the second harmonic generation of   polymethylmethacrylate films doped with 4-(4-nitrophenylazo)aniline   chromophores
  The kinetics of the orientation of Disperse Orange 3 molecules embedded in amorphous and nanostructured Polymethylmethacrylate films was studied under the effect of an intense electrostatic poling field. Non-centrosymmetric chromophore distributions were obtained in Polymethylmethacrylate films by Corona poling technique. These distributions depends on the Corona poling time. The changes in the orientation of the Disperse Orange 3 molecules were followed by in-situ transmitted Second Harmonic Generation measurements. The Second Harmonic Generation signal was recorded as function of time at several temperatures; it was fitted as function of the Corona poling time, considering matrix-chromophore interactions. The Polymethylmethacrylate films were nanostructured by the incorporation of an anionic surfactant, the Sodium Dodecyl Sulfate. The lamellar nanostructures in the films were identified by X-ray diffraction measurements. 
Alfredo Franco (1 and 2), Laura Romero-Miranda (1), Guadalupe   Valverde-Aguilar (1), Jorge Garc\'ia-Macedo (1), Giovanna Br...
physics.optics cond-mat.mes-hall