Crystal growth and thermal properties of the laser crystal Yb3+:Gd3(AlxGa1−x)5O12

Bulk single crystals of Yb3+:Gd3(AlxGa1−x)5O12 (Yb:GAGG) with dimensions of Φ26 mm×30 mm were successfully grown using the Czochralski method. The nominal Yb and Al contents in the raw materials were 5.0 and 10.0 at%, respectively. The effective segregation coefficients of Yb3+ and Al3+ ions were measured, and the doping concentrations of Yb3+ and Al3+ ions in the crystal were calculated to be 6.25-6.03 at% and 12.0-11.67 at% along the crystal growth direction, respectively. The crystalline perfection of the as-grown crystal was evaluated by high-resolution X-ray diffraction (HRXRD). The thermal properties, including thermal expansion, specific heat and thermal conductivity, have been studied in detail. In addition, the thermal-optical coefficient and the thermal shock resistance parameters were also calculated. Our results show that Yb:GAGG crystal has potential application in the field of high power solid state laser.