Er3+/Pr3+ co-doped GeAsGaSe chalcogenide glasses for infrared emissions and their potential in 2.7 mu m fiber laser

A series of Ge10As24Ga4Se62-xEr-yPr (x, y = 0, 0.1, 0.2, 0.3 mol%) chalcogenide glasses were fabricated and their suitability in optical materials was investigated. The optical and thermal properties of the glasses were analyzed by XRD, DSC and Raman. At the same time, the near-infrared (NIR) and mid-infrared (MIR) fluorescence spectra were also reported as well as their decays. The results showed that under the excitation of 980 nm, the introduction of Pr3+ can effectively shorten the decay time of Er3+: I-4(13/2) level from 2.34 ms to 0.31 ms. Therefore, the decay time of Er3+: I-4(13/2) is shorter than that of Er3+: I-4(1)1/2, and population inversion can be achieved. In addition, the laser characteristics of the fiber were studied by establishing a cascade laser model for numerical simulation. The output power of the 2.7 mu m laser can reach 0.43 W and the slope efficiency is 14.21% when the Er3+ and Pr3+ ions concentrations are 0.3 mol%, the excitation wavelength is 980 nm, and the pump power is 5 W, which shows that this system can be used in mid-infrared fiber lasers with great potential.