Examining the Spectroscopic and Thermographic Qualities of Er(3+)-doped Oxyfluoride Germanotellurite Glasses

Novel ternary fluoro-germano-tellurite (GTS) glasses doped with Er(3+) ions with 0.5 mol% and 1.0 mol% were fabricated by a conventional melt and quenching method and investigated using methods of optical spectroscopy. The room-temperature absorption spectrum was recorded and analyzed to determine radiative transition rates, radiative lifetimes, and branching ratios of Er(3+) luminescence. Decay curves of Er(3+) luminesccence were recorded and analyzed. Temperature dependences of emission spectra and absorption spectra in the region from RT (room-temperature) up to 675 K were studied in detail. The contribution of competing radiative and nonradiative processes to the relaxation of luminescent levels of Er(3+) was assessed. Absolute and relative sensitivity were established utilizing the comprehensive model based on thermally coupled (2)H(11/2)/(4)S(3/2) excited states of erbium. The high quantum efficiency of the first erbium-excited state and value of gain coefficient indicate that GTS:Er glass system can be considered as conceivable NIR (near infrared) laser material as well.