Sol-gel thin film deposition and characterization of a new optically active compound:: Er2Ti2O7

This paper reports on the first sol-gel thin film preparation of a new optically active compound: Er2Ti2O7 (ETO). Optical, microstructural and spectroscopic properties of ETO films annealed in a temperature range 300-1000 degreesC are studied. This work shows that the porosity and microstructure of ETO films depend closely on the heat-treatment temperature. Photoluminescence (PL) has been observed for films heat-treated at 600 degreesC or more. The PL decay appears strongly influenced by quenching effects. For thin films treated at 600 degreesC, quenching is essentially due to the presence of hydroxyl groups. After heat-treatment at 800 degreesC or more, quenching can be explained by the high concentration of erbium atoms and by their distribution in the ETO lattice. (C) 2001 Elsevier Science B.V. All rights reserved.