A Stable 22-W Low-Noise Continuous-Wave Single-Frequency Nd:YVO 4 Laser at 1.06 μm Directly Pumped by a Laser Diode

We report a low-noise continous-wave single-frequency Nd:YVO 4 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 2 x = 1.05 and M 2 y = 1.02. The intensity noise and the phase noise of the laser reach the shot-noise limit at an analysis frequency of 5 MHz.