Adjustable and stable beam profile generation in a Yb:YAG thin-disk laser

We present a Yb:YAG thin-disk laser with an adjustable and stable beam profile. A double-cavity geometry with an acousto-optic modulator (AOM) makes the spatial separation of the gain area, in which the central and external parts are used for LG(00) and LG(01) mode generation, respectively. By changing the loss of the AOM, the beam profile of the primary cavity is adjustable from annularity to fiat-top continuously. At input pump power of 44 W, 8.5 W annular, 11.1 W shallow crater-shaped, and 12.1 W flat-topped modes were obtained. Moreover, the thin-disk laser with a multi-pass pumping scheme not only improves thermal management, but also minimizes depolarization loss, allowing the optimization of mode stability and laser performances. This Letter implies that a high-power laser with an adjustable and stable beam profile can be implemented via this scheme. (C) 2020 Optical Society of America