4.0-4.5-mu m lasing of Fe : ZnSe below 180 K, a new mid-infrared laser material

Lasing of Fe:ZnSe is demonstrated, for the first time to the authors' knowl edge, for temperatures ranging from 15 to 180 K. The output wavelength of t he Fe:ZnSe laser was observed to tune with temperature from 3.98 mu m at 15 K to 4.54 mu m at 180 K. With an Er:YAG laser operating at 2.698 mu m as t he pump source, a maximum energy per pulse of 12 mu J at 130 K was produced . Laser slope efficiencies of 3.2% at 19 K and 8.2% at 150 K were determine d for an output coupling of 0.6%. A laser emission linewidth of 0.007 mu m at 3.98 mu m was measured at 15 K Absorption and emission spectra and emiss ion lifetimes for Fe:ZnSe are also discussed. (C) 1999 Optical Society of A merica.