Abstract:
In recent years, coherent detection lidar is an effective means to measure long-range low-altitude wind shear. 1.6 μm solid-state lasers have become the main light source for coherent radar with the advantages of human eye safety and mature detector devices. Its gain medium Er:YAG crystal had a strong absorption peak in the 1532 nm band, but the absorption spectrum was narrow, so the crystal output efficiency can be effectively improved by resonant pumping using a 1532 nm fiber laser. To this end, an all-fiber 1532 nm laser output was achieved with an Er/Yb double-clad fiber as the gain medium, a 1532 nm fiber grating as the reflective cavity mirror and a 976 nm semiconductor laser as the pumping source. The output laser had a maximum power of 73.44 W, a tunable wavelength range of 1531.35-1532.14 nm, a wavelength spectral width of 0.06 nm, and the beam quality M
2 of 1.38 and 1.26 in
x and
y direction, which was an ideal pumping source for 1.6 μm solid-state lasers. The laser was used to pump Er: YAG nonplanar ring cavity to obtain 1.3 W single frequency laser output, and the slope efficiency was 31.76%.