Edge multi-facet pumping configuration for thin gain lasers

In this article an edge-facet and multi aperture pumped thin gain laser with highly efficient and simple pump optics is reported. The crystal configuration is a symmetrical hexagonal Composite Yb:YAG/YAG with slanted sides. Three diodes are placed outside the hexagonal shape disk, and the emitting light is coupled via three lens ducts through its three slanted edges and propagates through the disk along the zigzag path and repeatedly passes the gain medium, thus pump uniformity and absorption efficiency are improved. A comprehensive numerical model is utilized in the laser designing process. 192 W output power with good beam quality was achieved from this laser configuration.

► An edge-pumped hexagonal double layer composite YbYAG/YAG laser is reported.
► Via strategic facets cut at the edges, pump photons are trapped and pass through gain media repeatedly.
► This configuration allows a reduced thickness of gain media while keeping the pump optics simple.
► In this structure, the ASE impact is minimized because YAG cap volume adjacent to Yb:YAG.
► Results show this geometry is a high efficient configuration for thin gain lasers.