Direct excitation of chirality controllable LG₀₁ vortex beam in solid-state lasers by intracavity astigmatism manipulation

In this letter, we report a systematic approach to directly generate chirality controllable Laguerre–Gaussian (LG₀₁) mode in solid-state lasers. This approach is based on two concepts. The first is the off-axis pumping technique, which has been exploited to achieve Hermite–Gaussian modes. The second is intracavity astigmatism manipulation, which has been introduced to the laser cavity by tilting curved mirrors to generate LG modes. The control method of chirality has been discussed in detail. The feasibility of this approach is shown in both theoretical model and experimental analysis of the generation process. (letter)