Nd:GYSGG laser at 1331.6 nm passively Q-switched by a Co:MgAl₂O₄ crystal

The CW and passively Q-switched operation of a Nd:GYSGG laser is demonstrated. In the CW operation, triple-wavelength lines at 1323.9, 1331.6 and 1336.8 nm are generated simultaneously. The maximum CW output power is 1133 mW under a pump power of 7.85 W. In the passively Q-switched operation, a Co:MgAl₂O₄ crystal with initial transmission of 82% is employed, only single-wavelength line at 1331.6 nm is realized. The narrowest pulse width of 20.5 ns is achieved with an output power of 225 mW under the same pump power. The highest peak power and pulse energy are 1319 W and 27.2 μJ under a pump power of 7.20 W, respectively.