400 mW low noise continuous-wave single-frequency Er,Yb:YAl3(BO3)4 laser at 1.55 μm.

We build up a LD end-pumped Er,Yb:YAB laser at 1.55 μm and improve the laser performance by end cooling the gain medium efficiently through a sapphire plate. 680 mW cw single transverse mode laser output was obtained with the slope efficiency of 16.3%. Using an etalon placed in the laser cavity, 400 mW cw single frequency 1.55 μm laser output was achieved with the slope efficiency of 11.8%. The laser power fluctuation was less than ± 1.3% in a given period of 1.5 hours. The 1.55 μm laser presents low noise properties, that the intensity and the phase noise reach the shot noise level for the analysis frequencies higher than 4 MHz and 5 MHz, respectively.