Brasselet E, Doyon B, Galstian T V, Dubé L J
Laboratoire de Photonique Quantique et Moléculaire, Ecole Normale Supérieure de Cachan, 94235 Cachan Cedex, France.
Phys Rev E Stat Nonlin Soft Matter Phys. 2004 Feb;69(2 Pt 1):021701. doi: 10.1103/PhysRevE.69.021701. Epub 2004 Feb 10.
We report on the influence of a finite beam size on the molecular reorientation dynamics when a nematic liquid crystal film is excited by a laser beam. We present experimental evidence of a new class of nonlinear dynamics when the excitation is a Gaussian shaped, circularly polarized laser beam at normal incidence. Various nonlinear regimes, periodic, quasiperiodic, intermittent, and possibly chaotic, are observed. A physical interpretation based on walk-off effects is proposed and its implications on current research in the field are discussed.
我们报告了在向列型液晶薄膜被激光束激发时，有限光束尺寸对分子重取向动力学的影响。当激发源是垂直入射的高斯形状圆偏振激光束时，我们给出了一类新型非线性动力学的实验证据。观察到了各种非线性状态，包括周期性、准周期性、间歇性以及可能的混沌状态。我们提出了基于走离效应的物理解释，并讨论了其对该领域当前研究的影响。
