Chromium lases at 2515 nm in new crystal host at room temperature
Doping a cadmium manganese telluride (Cd0.85Mn0.15Te) host with chromium enabled Uwe H?mmerich and others at Hampton University (Hampton, VA) in collaboration with Brimrose Corp. of America (Baltimore, MD) to demonstrate room-temperature pulsed laser operation of a new solid-state laser material that emits at 2515 nm. The material is easier to grow than the alternative chromium hosts?zinc selenide or zinc sulfide?and crystals as large as 3 cm in diameter can be produced. Brimrose engineers grew chromium-doped CdMnTe using the
vertical Bridgman-Stockbarger technique. Estimated Cr2+ concentration in the resultant
crystal was less than 2 1019 atoms/cm3.
The Hampton grou¥placed an uncoated 3.7-mm-thick, 21-mm-diameter sample in a
6-cm-long end-pumped cavity and excited it with the output from a Q-switched Nd:YAG laser Raman-shifted by a hydrogen cell to 1907 nm. Output of the Cr2+:CdMnTe system was
centered at 2515 nm (50 nm FWHM), with a slope efficiency of 5.5% above the threshold of 3.4 mJ. The results are preliminary?by altering the manganese content in the host, the researchers hope to optimize the laser performance of the material.