A Stable 22-W Low-Noise Continuous-Wave Single-Frequency Nd:YVO₄ Laser at 1.06 µm Directly Pumped by a Laser Diode

We report a low-noise continous-wave single-frequency Nd:YVO₄ laser at 1.06 µm directly pumped by an 880−nm laser diode. A maximum output power of 22 W is achieved with an optical-to-optical conversion efficiency of 46.3%. The stability of the output is better than ±0.7% in the given four hours. The output beam is almost diffraction−limited with a measured beam quality of M_x²=1.05 and M_y²=1.02. The intensity noise and the phase noise of the laser reach the shot-noise limit at an analysis frequency of 5 MHz.