Fabrication of highly ytterbium (Yb3+)-doped YAG thin film by pulsed laserdeposition

As an infrared laser waveguide, the epitaxial growth of 5 mum-thick ytterbi um (Yb3+)-doped yttrium aluminum garnet (YAG) thin films on YAG(1 1 1) (Y3A l5O12) substrate has been demonstrated by pulsed KrF laser deposition with postannealing. Highly Yb3+-doped (up to 100 at.%) YAG films have been epita xially grown on YAG(1 1 1). The crystalline quality of the grown films does not degrade even with high doping concentrations of Yb3+ ions up to 100 at .%. The roughness (root mean square) of the film is measured as 1.27 nm wit hout droplets or particulates. The optical properties of these films have b een characterized in terms of absorption spectra, fluorescence spectra and fluorescent lifetime. The refractive index of n at 1.03 mum is measured to be 1.851 +/- 0.0141 for 50 at.% Yb3+:YAG. An emission lifetime of 0.90 +/- 0.01 ms is obtained for 1.03 mum transition. (C) 2001 Elsevier Science B.V. All rights reserved.