Highly efficient 12  W diode-pumped actively Q-switched Yb:KGd(WO4)2 laser

A compact diode-pumped actively Q-switched Yb:KGW laser is demonstrated with an optical-to-optical efficiency of 50%. In a 3-mirror laser cavity configuration output power of 12.2 W with repetition rate up to 50 kHz and pulse duration of 10-24 ns was obtained. The maximum pulse peak power of 70 kW was achieved. The laser output beam profile was Gaussian up to maximum pump powers with M2 factor less than 1.2.