科研之友
微信
新浪微博
Facebook
分享链接
摘要
Anisotropic diffraction patterns were observed on far-field screen induced by a weak (approximate to 0.16 W/cm(2)) linearly polarized collimated beam passing through a homeotropic C(60)-doped nematic liquid crystal (5CB) cell. Based on orientational photorefractive effect, two-wave coupling experiment was carried out to induce liquid crystal molecule re-orientation. The form of space-charge field with the Gaussian distribution induced by the Gaussian beam incident on the sample is investigated. The outline of far-field diffraction pattern is concentric ring, and shows symmetrical gaps in the direction perpendicular to the direction of polarization of light. In addition, diffraction pattern changes when the polarization of the incident light is changed, effective nonlinear index coefficient is n(2) approximate to 0.3 cm(2)/W. The results showed that our theoretical analyzsis was consistent with the observed experimental phenomena.
