Development of a High-Quality Epoxy Bonding Technology

We reported an ytterbium-doped Y
₂
O
₃
disk with diameter of 11 mm and thickness of 1.2 mm bonded onto a copper heatsink by new high-quality epoxy bonding technology. The disk clear aperture with diameter of 9 mm has the radius of curvature equal to -1586 meters and peak-to-valley value lower than 60 nm. Gain medium with such parameters is ideal for high power laser systems operating in single spatial mode with a pump diameter larger than 3 mm.