理论分析了非局域程度对向列相液晶中(1+2)维空间光孤子的影响.得到了非线性系数以及特征长度和预倾角的关系,并且给出了强非局域性的非线性薛定谔方程,最终得到了单孤子和临界功率的解析解.实验上,通过改变偏压从而间接测量了向列相液晶中的临界功率,并与数值模拟结果相结合与理论结果进行了比较,发现基本相符.
In this paper, we theoretically investigated the influence of nonlocality on (1 + 2)-dimensional spatial solitons in undoped nematic liquid crystals (NLCs). We confirmed that the nonlinear index coefficient and the general characteristic length of the nonlinear nonloeality for the NLC are dependent on the pretih angle of the NLC molecules. Then the Schrodinger-type nonlinear equation in strong nonloeality was given and from the equation the analytical expressions of the single soliton and the critical power were respectively obtained. In experiment, we varied the degree of nonlocality by changing the bias voltage and indirectly determined the relation between the critical power and pretih angle. At last, by comparison of analytical solutions with the numerical simulation and the experimental result, we verified that our expressions are precise.