Efficient dual-end pumped a-cut Er:Yb:YAl3(BO3)4 microchip laser

This paper presents the findings of a high-efficiency continuous-wave (CW) microchip laser operating at 1.5 mu m, utilizing an a-cut Er:Yb:YAl3(BO3)4 (Er:Yb:YAB) crystal. The laser was effectively pumped using a dual-end co-polarization configuration. The temperature distribution within the Er:Yb:YAB crystal, as simulated through finite element analysis, substantiates the efficacy of the dual-end pumping approach in enhancing the thermal gradient within the crystal. A CW Er:Yb:YAB microchip laser with the maximum polarized output power of 2.79 W was obtained with the pump power of 16.2 W at the wavelength of 1531 nm. To the best of our knowledge, this is the largest CW polarized laser output power in the reported Er:Yb:YAB microchip laser. The beam quality factors of our output laser are M2x = 1.54 and M2y = 1.57, which shows better beam quality than single-end pumped Er:Yb:YAB microchip laser.