Thin film sol-gel fabrication and characterisation of a new optically active crystalline phase: Er/sub 2/Ti/sub 2/O/sub 7/

Summary form only given. A lot of research has been done to limit parasitic effects linked to the high rare earth doping levels necessary for all-optical amplifiers or integrated lasers. One original solution consists in doping a glass matrix with nanosized, erbium-containing crystals. Hence, one can choose the crystalline phase to optimise the spectroscopic properties, while the matrix is a material well suited for waveguiding. Recently, optically active silica-titania thin films containing ErPO/sub 4/ (EPO) and Er/sub 2/Ti/sub 2/O/sub 7/ (ETO) have been successfully elaborated. In order to study in more details these crystalline phases, pure ETO has been prepared and characterised. To the best of our knowledge this is the first spectroscopic study of pure ETO.