Red photoluminescence in praseodymium-doped titanate perovskite films epitaxially grown by pulsed laser deposition

Intense red photoluminescence (PL) under ultraviolet (UV) excitation was observed in epitaxially grown Pr-doped Ca0.6Sr0.4TiO3 perovskite films. The films were grown on SrTiO3 (100) substrates by pulsed laser deposition, and their epitaxial growth was confirmed by x-ray diffraction and reflected high-energy electron diffraction. The observed sharp PL peak centered at 610 nm was assigned to the transition of Pr3+ ions from the D-1(2) state to the H-3(4) state. The PL intensity was markedly enhanced by postannealing treatments at 1000 degrees C, above the film-growth temperature of 600 or 800 degrees C. Because the excitation and absorption spectra are similar to each other, it was suggested that the UV energy absorbed by the host lattice was transferred to the Pr ions, resulting in the red luminescence. (c) 2006 American Institute of Physics.