Solid-state laser with a high average output power and compensation of the optical inhomogeneities of the active medium

The energy characteristics and the spatial distributions of the radiation generated in the free-running lasing regime were investigated for a configuration (proposed previously by the authors) with compensation of the optical inhomogeneities in the active media of powerful solid-state lasers. Slab active elements made of Nd³⁺:KGd(WO₄)₂ and Nd³⁺:NaLa(MoO₄)₂ crystals were used. A uniform transverse intensity distribution in an output beam (37 mm × 8 mm in cross section) and a nearly limiting angular divergence were achieved for a pulse energy in excess of 60 J, a repetition rate up to 2 Hz, and a slope efficiency of 2.5%.