Spatial–Temporal Manipulations of Visible Pulsed Vortex Beams in a Q-Switched Pr:YLF Laser with a (PEA)2(CsPbBr3)n−1PbBr4 Perovskite Saturable Absorber

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Visible pulsed vortex beams with controllable temporal profiles and customizable transverse modes are of great scientific and practical interest. The generation of visible pulsed vortex beams from lasers remains a significant challenge due to the limited availability of well-developed saturable absorbers (SAs) in the visible spectrum. Here, we report the generation of 640 nm passively Q-switched vortex beams from a Pr:YLF all-solid-state laser, for the first time to the best of our knowledge, using quasi-2D (PEA) 2 (CsPbBr 3 ) n −1 PbBr 4 perovskites as the SA. Stable pulsed TEM 0,0 mode generation with a tunable pulse duration from 826.5 to 371.2 ns and a corresponding repetition rate from 63.7 to 121.3 kHz was achieved. Additionally, customizable transverse modes were generated from the Pr:YLF laser cavity using a noncollinear pumping technique to precisely manage the gain and loss characteristics of intracavity transverse modes. A first-order vortex beam at 640 nm was obtained through astigmatic mode conversion from the passively Q-switched Pr:YLF laser. These results present a new paradigm in generating visible pulsed vortex beams, offering excellent application potential in underwater communication and super-resolution imaging.