標題: SELF-BENDING AND ASYMMETRIC SPATIAL SELF-PHASE MODULATION EFFECTS IN NEMATIC LIQUID-CRYSTAL FILMS
作者: PAN, RP
CHEN, SM
PAN, CL
電子物理學系
光電工程學系
Department of Electrophysics
Department of Photonics
公開日期: 1-May-1991
摘要: Laser-induced beam bending and the far-field asymmetric diffraction ring pattern due to the self-bending and asymmetric spatial self-phase modulation (SPM) effects in nematic liquid-crystal films are investigated. The measured far-field patterns are in good agreement with numerical calculations based on the diffraction theory, taking into account the two dimensionally of the problem, the nonlocal effect, and the wave-front curvature effect. The individual contributions of the aforementioned effects to the far-field pattern are analyzed for the first time. It is shown that the outermost diffraction peak of the far-field pattern is not the strongest one and that a large fraction of the transmitted intensity remains in the central region (within +/- 6 mrad of the beam axis). Merging of some of the diffraction peaks in this region should also occur. Although the transmitted beam does deflect, the deflection angle does not increase monotonically with the incident laser intensity, as is the case for a purely Kerr-like medium. In the experiments discussed here, higher-order effects are present. As an example, it is shown that equally pronounced third- and fifth-order nonlinear optical SPM effects are responsible for an observed five-ring asymmetric ring pattern.
URI: http://dx.doi.org/10.1364/JOSAB.8.001065
http://hdl.handle.net/11536/3786
ISSN: 0740-3224
DOI: 10.1364/JOSAB.8.001065
期刊: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
Volume: 8
Issue: 5
起始頁: 1065
結束頁: 1071
Appears in Collections:Articles


Files in This Item:

  1. A1991FL11600022.pdf