Intense 2.1-4.2 µm broadband emission of Co/Er:PbF mid-infrared laser crystal.

A novel mid-infrared (MIR) laser crystal /: was successfully grown. The use of ion co-doping to sensitize a ion and enhance the 2.1-4.2 µm broadband MIR emission of the ion in a crystal was studied for the first time, to the best of our knowledge. The ion was demonstrated to be an effective sensitizer of the ion, making the /: crystal propitious to be pumped by commercialized laser diodes. Furthermore, with ion co-doping, the local symmetry of and ions was seriously distorted, thereby enhancing the 2.1-4.2 µm MIR emissions. This study provides a path for designing MIR laser materials with optimal performance.