Polar diffraction gratings have been prepared by spatially periodic photopoling Langmuir–Blodgettfilms consisting of azobenzene compounds. The gratings were made by film irradiation with two leftcircularly polarized Ar-ion laser beams under strong electric field from a corona discharge.Therefore, simultaneously with the spatial modulation of the linear refractive index, the local polarorder of the film becomes periodically modulated (through symmetry, the latter is related to themodulation of second-order optical nonlinearity x(2)). The local polarity is shown by an electrostaticforce microscopy technique: an image of the polar grating is recorded without any trace ofperiodicity in the film topography.
Polar diffraction gratings made by spatially periodic photo-poling Langmuir-Blodgett films
DE SANTO, Maria Penelope;G. CIPPARRONE;BARBERI, Riccardo Cristoforo
2002-01-01
Abstract
Polar diffraction gratings have been prepared by spatially periodic photopoling Langmuir–Blodgettfilms consisting of azobenzene compounds. The gratings were made by film irradiation with two leftcircularly polarized Ar-ion laser beams under strong electric field from a corona discharge.Therefore, simultaneously with the spatial modulation of the linear refractive index, the local polarorder of the film becomes periodically modulated (through symmetry, the latter is related to themodulation of second-order optical nonlinearity x(2)). The local polarity is shown by an electrostaticforce microscopy technique: an image of the polar grating is recorded without any trace ofperiodicity in the film topography.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
