Continuous-wave orange laser at 605.98 nm based on a diode-pumped Pr, Gd:SrF2 crystal

Orange laser source at 605.98 nm corresponding to 3H4 & RARR; 1D2 optical transition of the Pr3+ ions in Pr:Y2SiO5 crystal is very crucial for quantum information experiments, which was only provided by dye laser in previos experiments. Although optical parametric oscillators (OPOs) or frequency doubling may be utilized in these years, high-power laser diodes are not yet accessible at this wavelength, and neither have appropriate output powers nor frequency stability. In this work, Pr:SrF2 and Pr,Gd:SrF2 single crystals were grown by TGT method and the spectroscopic investigation was carried out systematically. By co-doping Gd3+ ions into Pr:SrF2 single crystal, the intensity of orange emission at about 606 nm is strengthened while the red emission is suppressed. The first demonstration of all-solid-state continuous-wave orange laser at this specific wavelength was first re-ported in Pr3+ doped SrF2 crystal, to the best of our knowledge. Moreover, by using an un-doped YAG etalon for wavelength tuning, the orange emission of Pr,Gd:SrF2 laser showed certain wavelength tunability, which in-dicates Pr,Gd:SrF2 crystal could be promising for generation of ultrashort pulse laser in visible region.