Energy transfer up-conversion in Tm3+-doped silica fiber

• Published in: Journal of non-crystalline solids Vol. 352; no. 2; pp. 136 - 141
• Main Authors: Simpson, D.A., Baxter, G.W., Collins, S.F., Gibbs, W.E.K., Blanc, W., Dussardier, B., Monnom, G.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.02.2006; Elsevier
• Subjects: Absorption; Alumino-silicates; Amorphous materials, glasses and other disordered solids; Applied sciences; Circuit properties; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electric, optical and optoelectronic circuits; Electronics; Exact sciences and technology; Integrated optics. Optical fibers and wave guides; Luminescence; Optical and optoelectronic circuits; Optical fibers; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical spectroscopy; Photoluminescence; Physics; Rare-earths in glasses; Silica; Time resolved measurements; Up-conversion; Optical fibers; Optical spectroscopy; 33.50.−j; Absorption; Alumino-silicates; 32.70.Cs; Rare-earths in glasses; 31.70.Hq; Luminescence; Time resolved measurements; Silica; Up-conversion; Doping; Photoluminescence; Frequency conversion; Silicates; Glass fibers; Energy-level transitions; Pumping; 33.50.-1 Optical fibers; Two-photon processes; Rare- earths in glasses; Thulium additions; Excited states; Time resolved spectra; Rate equation; Energy transfer
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/j.jnoncrysol.2005.11.019

A study of the mechanisms responsible for the infra-red to near infra-red up-conversion in Tm3+-doped silica fibers is presented. Up-conversion luminescence was observed from the 3H4 level of Tm3+ under 1586nm pumping into the 3F4 level. The quadratic dependence of the up-conversion luminescence at 800nm on the 1800nm luminescence from the 3F4 level confirms that the 3H4 level is populated by a two photon process. Two possible processes are proposed as mechanisms responsible for the up-conversion: excited state absorption and energy transfer up-conversion. The decay characteristics of the luminescence from the 3H4 level were studied under direct and indirect pumping at 786 and 1586nm, respectively. By comparing the decay waveforms to the solution of a simple set of rate equations, the energy transfer up-conversion process (3F4, 3F4→3H4, 3H6) was established at Tm2O3 concentrations greater than 200ppm.