Laser performance of disordered Yb:Ca3(NbGa)2-xGa3O12 crystal under diode pumping at 974-976 nm

Efficient continuous-wave (CW) laser operation is demonstrated at room temperature with disordered Yb:Ca-3(NbGa)(2-x)Ga3O12 crystal by diode pumping at 974-976 nm. With 2.0 W of pump power absorbed in a 1.5 mm thick crystal, a CW output power of 0.62 W is generated, resulting in an optical-to-optical efficiency of 31%, while the slope efficiency amounts to 50%. Upon increasing the pump power to a high level, a transient process takes place, in which the output power decreases continuously towards its stationary value. [GRAPHICS] Relationship between P-oul and P-abs measured in the transient process of power reduction, giving rise to a slope efficiency of eta = 60%