Cr4+:Gd3Sc2Ga3O12 passive Q‐switch for the Cr3+:LiCaAlF6 laser

A Cr4+:Gd3Sc2Ga3O12 (Cr4+:GSGG) broad‐band saturable absorber has been demonstrated to be an excellent passive Q‐switch for the flashlamp‐pumped tunable Cr3+:LiCaAlF6 (Cr:LiCAF) laser at room temperature. A single Q‐switched laser output pulse of 11 mJ in energy and 37 ns in duration at 778 nm was obtained in a nonoptimized laser.