NIR to visible up-conversion, infrared luminescence, thermoluminescence and defect centres in Y2O3 : Er phosphor - Singh, Vijay; Rai, Vineet Kumar; Ledoux-Rak, Isabelle; Watanabe, Shigueo; Rao, T K Gundu; Chubaci, José Fernando Diniz; Badie, Laurent; Pelle, Fabienne; Ivanova, Svetlana (Journal of Physics D - Applied Physics, 2009)