In situ growth of optically active erbium doped Al2O3 thin films by pulsed laser deposition

3 pages, 3 figures.-- PACS: 81.15.Fg; 78.66.Nk; 78.55.HxThin Al2O3 films are grown and in situ doped with erbium by pulsed laser deposition in a single step process, by alternate ablation from Al2O3 and Er targets. The as-deposited films have an Er step dopant profile throughout the film thickness, whose concentration depends on the number of pulses at the Er target. The as-grown films are optically active, as evidenced by the photoluminescence spectrum centered at 1.533 µm, corresponding to intra-4f transitions in Er3 + . The photoluminescence intensity increases upon annealing due to an increase of the luminescence lifetime. This is most likely a result of a decrease in the nonradiative decay channels, related to annealing of defects in the Al2O3 film.We thank A. Polman for his support during the development of this work and provision of experimental facilities at FOM-AMOLF, Amsterdam (the Netherlands). This work has been partially supported by CICYT under TIC-93 program (Spain). R.S. thanks the CAM (Communidad Autonoma de Madrid) for traveling finances.Peer reviewe