近年来，携带轨道角动量的涡旋光束在激光加工、光学微粒操纵、超分辨成像、大容量光通信等领域应用广泛，目前已在稀土掺杂光纤激光器中得到了广泛研究。基于声致光纤光栅，实验搭建了全光纤结构拉曼光纤激光器，实现LP₀₁模与LP₁₁模的有效调控，并进一步通过偏振控制实现环形径向偏振光和拓扑荷数l=±1的涡旋光束输出，最高输出功率~70 W，中心波长为1134 nm。文中提出的激光器有利于拓宽涡旋光束输出波段，在多维光通信、光场和物质相互作用等领域具备较大研究价值和应用潜力。

An all-fiberized random distributed feedback Raman fiber laser (RRFL) with LP11 mode output at 1134 nm has been demonstrated experimentally, where an intracavity acoustically induced fiber grating is employed for modal switching. The maximum output power of LP11 mode is 93.8 W with the modal purity of 82%, calculated by numerical mode decomposition technology based on stochastic parallel-gradient descent algorithm. To our best knowledge, this is the highest output power with high purity of LP11 mode generated from the RRFL. This work may pave a path towards advanced fiber lasers with special temporal and spatial characteristics for applications.

A hundred-watt-level spatial mode switchable all-fiber laser is demonstrated based on a master oscillator power amplifier scheme. The performance of the amplifier with two seed lasers, i.e., with the acoustically induced fiber grating (AIFG) mode converter inside and outside the seed laser cavity, is investigated. Real-time mode switching with millisecond scale switching time between the LP01 and LP11 modes while operating in full power (>100W) is realized through an AIFG driven by radio frequency modulation. This work could provide a good reference for realizing high-power agile mode switchable fiber lasers for practical applications.