TY - JOUR
T1 - Analysis of optically induced refractive index change of dye-doped nematic liquid crystals
AU - Shishido, A.
AU - Shih, M. Y.
AU - Khoo, I. C.
N1 - Funding Information:
This work is supported by the Army Research Office and the Penn State MRSEC Center for Collective Phenomena in Restricted Geometries under National Science Foundation grant DMR-0080019.
PY - 2002/3
Y1 - 2002/3
N2 - We present a detailed quantitative experimental and theoretical study of laser induced refractive index changes in nematic liquid crystals doped with methyl-red, disperse red and azobenzene liquid crystal. These refractive index changes, originating from molecular reorientations and order parameter modification, are measured by means of intensity and polarization grating methods. The reorientation of the director axis is calculated from polarization dependence of the probe beam diffraction efficiency. The contribution of each effect to the total diffraction efficiency is quantitatively evaluated. In general, we found that the reorientational direction of the NLC molecules depends on the dopants as well as the nature of the pump beam polarization state. In methyl-red doped samples, the laser induced reorientation mechanism dominates, whereas order parameter modification plays a major role in the others.
AB - We present a detailed quantitative experimental and theoretical study of laser induced refractive index changes in nematic liquid crystals doped with methyl-red, disperse red and azobenzene liquid crystal. These refractive index changes, originating from molecular reorientations and order parameter modification, are measured by means of intensity and polarization grating methods. The reorientation of the director axis is calculated from polarization dependence of the probe beam diffraction efficiency. The contribution of each effect to the total diffraction efficiency is quantitatively evaluated. In general, we found that the reorientational direction of the NLC molecules depends on the dopants as well as the nature of the pump beam polarization state. In methyl-red doped samples, the laser induced reorientation mechanism dominates, whereas order parameter modification plays a major role in the others.
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U2 - 10.1142/S0218863502000900
DO - 10.1142/S0218863502000900
M3 - Article
AN - SCOPUS:0036510499
SN - 0218-8635
VL - 11
SP - 1
EP - 12
JO - Journal of Nonlinear Optical Physics and Materials
JF - Journal of Nonlinear Optical Physics and Materials
IS - 1
ER -