Chromium Doped Yttrium Aluminum Garnet (Cr4+: YAG) is an excellent material for passively Q-switching diode pumped or lamp-pumped Nd:YAG, Nd:YLF, Nd:YVO4 or other Nd/Yb doped lasers at wavelength 0.8~1.2 μm. Cr4+: YAG might replace traditional material, such as LiF, organic Dye and color centers due to its advantages such as: being chemically stable, durable, UV resistant, having good thermal conductivity and high damage threshold (＞500 MW/cm2 ), and being easy to be operated. WISOPTIC provides Cr4+:YAG with Cr4+ doping level of 0.5~3 mol% and with cross sections from 2 × 2 mm2 to 14 × 14 mm2 and length from 0.1 mm to 12 mm. The initial transmission is 10% ~92% according to customers’ requirements.

The pulse width of passively Q-switched lasers could be as short as 5 ns for diode pumped Nd:YAG lasers and the repetition could be as high as 10 kHz for diode pumped Nd:YVO₄ lasers. Through Cr⁴⁺:YAG, efficient green output at 532 nm and UV output at 355 nm and 266 nm can be generated after a subsequent intracavity SHG in KTP or LBO, THG and FOHG in LBO and BBO for diode pumped and passively Q-switched Nd:YAG and Nd:YVO₄ laser.

Cr⁴⁺:YAG also can generate tunable output from 1.35 µm to 1.55 µm, as well as ultrashort pulse output when pumped by Nd:YAG laser at 1.064 µm.