We investigate numerically and analytically light propagation in a single spiral waveguide formed in a nonlinear dielectric medium, in the regime of low spatial frequency of the waveguide rotation. We present a general variational approach for computing soliton parameters analytically, which includes various types of nonlinearity. In the particular case of media with cubic-quintic nonlinearity, analytical expressions found are in very good agreement with the numerical findings.

中文翻译：

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光沿螺旋波导传播：变分法

我们在波导旋转的低空间频率范围内对非线性电介质中形成的单个螺旋波导中的光传播进行数值和分析研究。我们提出了一种用于分析计算孤子参数的通用变分方法，其中包括各种类型的非线性。在具有三次-五次非线性的介质的特殊情况下，发现的解析表达式与数值发现非常一致。