We study transverse dynamics of the optical field, generated in a single-frequency laser of moderate Fresnel number. The existence of steadily rotating vortex clusters generated spontaneously in laser with degenerate in frequency cavity is demonstrated numerically and experimentally in laser-like two-wave-mixing photorefractive oscillator with plane-mirror cavity and controlled aperture. The observed rotational dynamics of two-, three- and four-vortex clusters is explained within the framework of the general nonlinear pattern forming model.

中文翻译：

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旋转多涡旋激光束的产生

我们研究在中等菲涅尔数的单频激光器中产生的光场的横向动力学。在具有平面镜腔和受控孔径的类似激光的两波混合光折变振荡器中，通过数值和实验证明了在频率腔简并的激光器中自发产生的稳定旋转涡团的存在。在一般的非线性图案形成模型的框架内解释了观察到的两个，三个和四个涡旋簇的旋转动力学。