Charge Transfer Luminescence of Yb3+ in Orthophosphates

Abstract Charge transfer luminescence of Yb3+ in the orthophosphates REPO4 (RE=Sc, Lu, Y, La) has been investigated. Yb3+ shows charge transfer luminescence in the orthophosphates of cations with a relative small radius (Sc, Lu, Y). In LaPO4, no proof for Yb3+ charge transfer luminescence has been found. The decay time of the charge transfer luminescence is about 150 ns in the three orthophosphates. The quenching temperature is around 250 K and is compared with the quenching temperature of Eu3+ luminescence in the orthophosphates after excitation in the charge transfer state.