Crystal growth and luminescence properties of Yb-doped aluminate, gallate, phosphate and vanadate single crystals

(Lu1-xYbx)3Al5O12 (Yb:LuAG) (Y1-xYbx)AlO3 (Yb:YAP) (Y0.9Yb0.1)VO4 (Yb:YVO) and Ca8(La1.98Yb0.02)(PO4)6O2 (Yb:CLPA) single crystals were grown from the melt. Typical double peak spectrum of the Yb3+ Charge Transfer (CT) luminescence was observed in Yb-doped LuAG and YAP. Strong dependence of decay time and intensity on temperature was observed. Concentration quenching effect in Yb-rich Yb:YAP samples results in pronounced 1/e decay time shortening below 230 K, while above this temperature the decay curves are shaped mostly by the thermal quenching process. Double peak emission spectrum was not observed in Yb:YVO and Yb:CLPA. In the case of CLPA, under excitation in the Yb3+ CT absorption band round 270 nm both the fast (6 ns decay time) and slow components (about 150 μs+600 μs decay times) are observed at room temperature. CLPA emission intensity was not decreasing with temperature between 80 and 300 K. Mixing of the Yb3+ CT and CLPA excitonic states is proposed to explain this interesting phenomenon