The basic mechanisms of photo-induced space charge field formation, director axis re-orientation, and refractive index changes in fullerene C60- and dye-doped nematic liquid crystals films are presented. In particular, in aligned methyl-red-doped nematic liquid crystal film, we observe a nonlinear index change coefficient as high as 10 cm2/W, associated with purely optically induced liquid crystal director axis re-orientation. Experimental observations of dynamic and high-resolution storage holographic grating formation, two beam coupling with gain of nearly 3000 cm-1, optical limiting action at nanowatt cw laser power, and incoherent-coherent image conversion at μW/cm2 light intensity level are discussed.
Dye-doped Photorefractive Liquid Crystals for Dynamic and Storage Holographic Grating Formation and Spatial Light Modulation / I. C., Khoo; M. Y., Shih; M. V., Wood; B. D., Guenther; P. H., Chen; Simoni, Francesco; S. S., Slussarenko; Francescangeli, Oriano; Lucchetti, Liana. - In: PROCEEDINGS OF THE IEEE. - ISSN 0018-9219. - STAMPA. - 87:11(1999), pp. 1897-1911. [10.1109/5.796353]
Dye-doped Photorefractive Liquid Crystals for Dynamic and Storage Holographic Grating Formation and Spatial Light Modulation
SIMONI, Francesco;FRANCESCANGELI, ORIANO;LUCCHETTI, Liana
1999-01-01
Abstract
The basic mechanisms of photo-induced space charge field formation, director axis re-orientation, and refractive index changes in fullerene C60- and dye-doped nematic liquid crystals films are presented. In particular, in aligned methyl-red-doped nematic liquid crystal film, we observe a nonlinear index change coefficient as high as 10 cm2/W, associated with purely optically induced liquid crystal director axis re-orientation. Experimental observations of dynamic and high-resolution storage holographic grating formation, two beam coupling with gain of nearly 3000 cm-1, optical limiting action at nanowatt cw laser power, and incoherent-coherent image conversion at μW/cm2 light intensity level are discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
