Mid-infrared lasing from Ho 3+ in bulk InF 3 glass

We report on an Ho3+:InF3 glass laser pumped by a Cr3+:LiSAF laser emitting at 889 nm. Ho3+:InF3 glass is a promising material for direct mid-infrared lasers around 4 μm. To evaluate the performances of this new material, we compared it to an Ho3+:BYF crystalline laser pumped by the same source. At 650 mJ pump energy, 7.2 mJ (46 mJ) was obtained with Ho3+:InF3 (Ho3+:BYF), respectively. This is, to the best of our knowledge, the first reported laser activity in this type of glass.