Eye-Safe Er:YAG Laser Q-Switched by Co:Spinel Saturable Absorber

The aim of this work was to investigate the utilization of Co:Spinel as saturable absorber for eye-safe Er:YAG laser generating at 1645 nm wavelength. Co:Spinel (Co:MgAl2O4, Co:MALO) absorber is used to Q-switching for laser systems generating about 1.5 μm wavelength, for example for Er:glass laser. Due to lower radiation absorption above the 1.55 μm wavelength of Co:spinel, the another passive absorbers were investigated, e.g. U:SrF2[1], Co:GSGG [2], and Cr:ZnSe [3]. However, the advantage of Co:Spinel is its high damage threshold and therefore, the research of its utilization would be prolonged, especially for 1.6 μm Er:YAG laser.