80SiO2-20LaF3 oxyfluoride glass ceramic coatings doped with Nd3+ for optical applications

Transparent glass ceramic (GC) films and self-supported layers of composition 80SiO-20LaF doped with Nd were prepared by sol-gel method for the first time. GC films were deposited by dip coating on different substrates and heat-treated between 350°C and 850°C for 1, 3, and 80 hours. The structural analysis of thin films was performed by GI-XRD and HR-TEM to check the LaF nanocrystals precipitation in the SiO matrix, revealing a crystal size lower than 5 nm. The emission and excitation spectra and lifetimes of the films have been obtained for different thermal treatments and Nd contents. The luminescence intensity of the F →I laser transition increases with the treatment temperature and Nd content, whereas a reduction for the luminescence lifetime is observed compared to those observed in bulk samples prepared by melting quenching.This work was supported by MINECO sunder Projects No. MAT2013‐48246‐C2‐1‐P and MAT2013‐48246‐C2‐2‐P and Basque Country University PPG17/07. J.J. Velázquez also acknowledges MINECO under Grant FPDI‐2013‐16895.Peer Reviewe