The fluorescence dynamics from excited states of Er<sup>3+</sup> in KY(WO<sub>4</sub>)<sub>2</sub> are compared with Judd–Ofelt-theory calculations, and spectroscopic parameters of the promising laser transitions from the <sup>4</sup>I<sub>13/2</sub>, <sup>4</sup>I<sub>11/2</sub>, and <sup>4</sup>S<sub>3/2</sub> levels are determined. The cw excited-state absorption spectra of Er<sup>3+</sup>-doped KY(WO<sub>4</sub>)<sub>2</sub> are measured with a pump-and-probe technique and analyzed in the spectral range from 500 nm to 1800 nm. Energy transfer between Yb<sup>3+</sup> and Er<sup>3+</sup> ions in codoped KY(WO<sub>4</sub>)<sub>2</sub> is investigated. Laser action near 1.54 μm under Ti:sapphire and diode-laser pumping is obtained in Er, Yb:KY(WO<sub>4</sub>)<sub>2</sub>.
© 1998 Optical Society of America
N. V. Kuleshov, A. A. Lagatsky, A. V. Podlipensky, V. P. Mikhailov, A. A. Kornienko, E. B. Dunina, S. Hartung, and G. Huber, "Fluorescence dynamics, excited-state absorption, and stimulated emission of Er3+ in KY(WO4)2," J. Opt. Soc. Am. B 15, 1205-1212 (1998)