Yb:YAG is one of the most promising laser-active materials and more suitable for diode-pumping than the traditional Nd-doped systems. Compared with the commonly used Nd:YAG crsytal, Yb:YAG crystal has a much larger absorption bandwidth to reduce thermal management requirements for diode lasers, a longer upper-laser level lifetime, three to four times lower thermal loading per unit pump power. Yb:YAG crystal is expected to replace Nd:YAG crystal for high power diode-pumped lasers and other potential applications.

■ Advantages of Yb:YAG Crystals：

Very low fractional heating, less than11%
Very high slope efficiency

Broad absorption bands, about 8nm@940nm

No excited-state absorption or up-conversion
Conveniently pumped by reliable InGaAs diodes at 940nm (or 970nm)
High thermal conductivity and large mechanical strength
High optical quality