We present experimental results that demonstrate the great efficiency of a core-doped Nd:YAG rod (a hexagonal Nd:YAG core surrounded by undoped YAG) in producing high output power and excellent beam quality. An additional improvement in beam quality is clearly observed when the core-doped rod is used in combination with a LiF:F<sub>2</sub><sup>−</sup> crystal, which acts as a passive <i>Q</i>-switching element. This improvement is quantified by beam-propagation factors as low as <i>M</i><sup>2</sup> ≅ at a maximum average output power of 9 W. We show that transversally pumped core-doped rods with the addition of LiF:F<sub>2</sub><sup>−</sup> crystals fulfill the requirements for high-beam-quality, scalable, compact all-solid-state lasers in passively <i>Q</i>-switched operation.
© 1999 Optical Society of America
Antonio Lucianetti, Rudolf Weber, Walter Hodel, Heinz Peter Weber, Alexander Papashvili, Vladimir A. Konyushkin, and Tasoltan T. Basiev, "Beam-Quality Improvement of a Passively Q-Switched Nd:YAG Laser with a Core-Doped Rod," Appl. Opt. 38, 1777-1783 (1999)