A barium tungstate anti-Stokes Raman laser

Abstract

Stimulated Raman scattering (SRS) is one of most efficient methods for generating new laser lines. In recent years, SRS in crystalline Raman media have attracted much attention for the advantages of high Raman scattering gain, favorable thermal conductivity and good mechanical and chemical stability [1-3]. So far most crystalline Raman lasers focus on Stokes generation. In contrast to Stokes generation, ant-Stokes generation is a four-wave mixing process, which involves two pumping photons, one Stokes photon, and one anti-Stokes photon. A few researches with regard to crystalline anti-Stokes lasers have been reported before [4, 5]. In 2009, Mildren et al. reported a parametric Raman anti-Stokes laser at 508 nm based on KGd(WO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</inf> ) <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> crystal [5]. 1 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">st</sup> anti-Stokes output energies up 0.27 mJ were obtained with the conversion efficiency of 0.46%. In this letter, a BaWO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</inf> anti-Stokes Raman laser pumped by an actively Q-switched Nd:YAG laser at 1064 nm is presented for the first time.