1532 nm sensitized luminescence and up-conversion in Yb,Er:YAG transparent ceramics

Luminescent properties of Yb,Er:YAG transparent ceramics containing 5 at% Yb3+ and 0.5, 1 and 1.5 at%, respectively, Er3+ ions have been studied. It has been found that increasing of erbium ions concentration increases both efficiency of nonradiative energy transfer Yb3+→Er3+ (which reaches 72% for 1.5 at% Er3+) and the luminescence in the range of 650-700 nm associated with 4F9/2, 11/2 → 4I15/2 transitions of Er3+ ions. It was also determined that the concentration quenching of sensitized luminescence of Er3+ ions at 1532 nm is associated with secondary excitation of metastable energy level of Er3+ followed by up-conversion emission.