Cr:YAG for Solid-State High Power Passive Q-Switching

Cr:YAG (Chromium doped Ytterium Aluminum Garnet, Cr:Y₃Al₅O₁₂)  crystal is an excellent material for passive Q-switching of Nd:YAG and  other Nd or Yb doped lasers in the wavelength range of 0.8 to 1.2 μm. One of the remarkable features of Cr:YAG is its high damage threshold (500-1000 MW/cm²). Its absorption band extends from 800 nm to 1200 nm and peaks at around 1060nm with a very large absorption cross section.  Passive Q-switched lasers incorporating Cr:YAG crystals have been  extensively fabricated at low cost and with reduced system size and  weight.

Advantages of Cr:YAG crystal:

• Well proven as a passive Q-switch

• Excellent physical properties - chemically stable, good thermal conductivity and high damage threshold

• High optical SHG conversion

By using Cr:YAG, 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. Furthermore, an efficient output at 532 nm, 355 nm or 266 nm can be generated by a subsequent intracavity SHG in KTP or LBO, or THG/FOHG in LBO or BBO for diode pumped and passively Q-switched Nd:YAG or Nd:YVO₄ laser. Cr:YAG is also a laser crystal with tunable output from 1.35 µm to 1.55 µm, and can be used to make ultrashort pulse (ps or fs) laser when pumped by Nd:YAG laser at 1064 nm.

Application examples

• Passively Q-switched lasers operating at 1µm - Nd and Yb doped YAG, YLF an YVO₄ (for laser rangefinders, LIDAR, and LIBS systems)

• Laser systems where short pulses are required

WISOPTIC Specifications of Cr⁴⁺: YAG Crystal