Rectangular double-clad fibre laser with two-end-bundled pump
The two ends of an Nd-doped rectangular double-clad fibre are bundled together to achieve efficient matching with a 10 W fibre coupled LD. With such a configuration, ~5.4 W pump light is launched into the first-cladding, and 2.5 W laser output is obtained. A slope efficiency of 51% with respect to launched pump power has been achieved.