Dynamic grating features for the surface-induced photorefractive effect in undoped nematics

Abstract

We investigate the highly sensitive surface-induced photorefractive gratings, observed in undoped nematic planar cells for low dc voltage (few volts) and laser intensity (few milliwatts per square centimeter). Forced-light-scattering and two-beam coupling measurements on E7 nematic samples, aligned with rubbed polyvinyl alcohol layers, verify the orientational effect of a space-charge field and the crucial role of the polymer–liquid-crystal interface in the photoinduced processes, through a wavelength-dependent photoelectric activation. The experimental behavior supports the surface-induced photorefractive effect model, according to which light with the proper wavelength locally reduces the interfacial charge density, thus producing a space-charge electric field in the cell.

© 2004 Optical Society of America

Optical two-beam coupling for a surface-induced photorefractive effect in undoped liquid crystals

Pasquale Pagliusi and Gabriella Cipparrone
Opt. Lett. 28(23) 2369-2371 (2003)

Surface-induced photorefractivity in twistable nematics: toward the all-optical control of gain

P. Pagliusi, C. Provenzano, and G. Cipparrone
Opt. Express 16(21) 16343-16351 (2008)

Photorefractive effect in nematic—clay nanocomposites

Yuan-Pin Huang, Tsung-Yen Tsai, Wei Lee, Wei-Kuo Chin, Yun-Min Chang, and Hui-Yu Chen
Opt. Express 13(6) 2058-2063 (2005)

Hidden surface photorefractive gratings in a nematic-liquid crystal cell in the absence of a deposited alignment layer

Platon P. Korneychuk, Oleksandr G. Tereshchenko, Yuriy A. Reznikov, Victor Yu. Reshetnyak, and Kenneth D. Singer
J. Opt. Soc. Am. B 23(6) 1007-1011 (2006)

Electrically controlled surface diffraction gratings in nematic liquid crystals

J. Zhang, V. Ostroverkhov, K. D. Singer, V. Reshetnyak, and Yu. Reznikov
Opt. Lett. 25(6) 414-416 (2000)