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

• Continuous-wavelength laser operation has been achieved with the maximum output power of 47 mW and the initial slope efficiency of 4.4% on 0.6Pr,1.2Gd:SrF 2 single-crystal. • The first report about the CW laser output on Pr-doped SrF 2 crystal in orange region related to 3P 0 -3H 6 transition. • The bandwidth of absorption and emission is found to be 11 nm and 8 nm, respectively, which is the highest one among as-reported crystals. The study of Pr3+ ion doped visible light laser crystals with wide spectral luminescence characteristics is of great significance for the exploration of new ultrafast laser materials in the future. Orange laser source at 605.98 nm corresponding to 3H 4 → 1D 2 optical transition of the Pr3+ ions in Pr:Y 2 SiO 5 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:SrF 2 and Pr,Gd:SrF 2 single crystals were grown by TGT method and the spectroscopic investigation was carried out systematically. By co-doping Gd3+ ions into Pr:SrF 2 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 reported in Pr3+ doped SrF 2 crystal, to the best of our knowledge. Moreover, by using an un-doped YAG etalon for wavelength tuning, the orange emission of Pr,Gd:SrF 2 laser showed certain wavelength tunability, which indicates Pr,Gd:SrF 2 crystal could be promising for generation of ultrashort pulse laser in visible region. [ABSTRACT FROM AUTHOR]