Enhanced 3.9 µm emission from diode pumped Ho/Eu codoped fluoroindate glasses.

The use of codoping for enhancing the :→ emission in fluoroindate glasses shows that could depopulate the lower laser state : while having little effect on the upper state :, resulting in greater population inversion. The / codoped glass has high spontaneous transition probability (6.31) together with large emission cross section (7.68×10). This study indicates that codoping of with is a feasible alternative to quench the lower energy level of the 3.9 µm emission and the / codoped fluoroindate glass is a promising material for efficient 3.9 µm fiber lasers.