Numerical Design on Blue Diode Pumping of Deep-Red Lasers in Ho 3+ /Tb 3+ Co-Doped Fluoride Fibers

This is the authors' abstract. We don't add key points for this paper.

In this study, the performance of a continuous-wave (CW) deep-red Ho3+/Tb3+co-doped fluoride fiber laser was numerically investigated. The laser operated at approximately 750 nm and was cladding pumped by a blue diode. The laser slope efficiency is studied and discussed in relation to the effects of fiber length, output mirror reflectivity, and pump wavelength. The results indicate that Tb3+ions can assist the Ho3+:5F4+5S2→5I7transition in overcoming the population inversion bottleneck, resulting in a significant increase in efficiency and power scalability. At a launched pump power of 60 W, the calculated CW output power of 30.86 W was associated with a slope efficiency of 52%. Such a result encourages the development of a deep-red laser that is constructed from a fluoride fiber co-doped with Ho3+and Tb3+.