Visible to infrared energy conversion in Pr3+–Yb3+ co-doped fluoroindate glasses

• Published in: Optical materials Vol. 35; no. 12; pp. 2085 - 2089
• Main Authors: Borrero-González, L.J., Galleani, G., Manzani, D., Nunes, L.A.O., Ribeiro, S.J.L.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 01-10-2013; Elsevier
• Subjects: Cross relaxation; Direct power generation; Emission; Emittance; Energy transfer; Exact sciences and technology; Fluoroindate glasses; Frequency conversion ; harmonic generation, including high-order harmonic generation; Frequency down-conversion; Fundamental areas of phenomenology (including applications); Glass; Infrared; Lanthanides; Nonlinear optics; Optics; Photons; Physics; Frequency down-conversion; Lanthanides; Energy transfer; Fluoroindate glasses; Photoluminescence; Glass; Doped materials; Excitation energy transfer; Luminescence decay; Ytterbium additions; Infrared radiation; Excitation spectrum; Optical frequency conversion; Nonlinear optics; Codoping; Photon emission
• ISSN: 0925-3467; 1873-1252
• DOI: 10.1016/j.optmat.2013.05.024

•Good optical quality fluoroindate glasses have been prepared containing Pr3+ and Yb3+.•Potential application in c-Si solar cells with the conversion of visible light into infrared light.•Frequency conversion was studied and down-conversion and down shifting processes could be well identified.
Processes involving visible to infrared energy conversion are presented for Pr3+–Yb3+ co-doped fluoroindate glasses. The emission in the visible and infrared regions, the luminescence decay time of the Pr3+:3P0→3H4 (482nm), Pr3+:1D2→3H6 (800nm), Yb3+:2F5/2→2F7/2 (1044nm) transitions and the photoluminescence excitation spectra were measured in Pr3+ samples and in Pr3+–Yb3+ samples as a function of the Yb3+ concentration. In addition, energy transfer efficiencies were estimated from Pr3+:3P0 and Pr3+:1D2 levels to Yb3+:2F7/2 level. Down-Conversion (DC) emission is observed due to a combination of two different processes: 1-a one-step cross relaxation (Pr3+:3P0→1G4; Yb3+:2F7/2→2F5/2) resulting in one photon emitted by Pr3+ (1G4→3H5) and one photon emitted by Yb3+ (2F7/2→2F5/2); 2-a resonant two-step first order energy transfer, where the first part of energy is transferred to Yb3+ neighbor through cross relaxation (Pr3+:3P0→1G4; Yb3+:2F7/2→2F5/2) followed by a second energy transfer step (Pr3+:1G4→3H4; Yb3+:2F7/2→2F5/2). A third process leading to one IR photon emission to each visible photon absorbed involves cross relaxation energy transfer (Pr3+:1D2→3F4; Yb3+:2F7/2→2F5/2).