Diode-pumped continuous-wave a- and c-cut Pr:Sr0.5La0.5Mg0.5Al11.5O19 (Pr:ASL) visible lasers at 645 and 726 nm

Abstract : Pr$^{3+}$-doped Sr$_{0.5}$La$_{0.5}$Mg$_{0.5}$Al$_{11.5}$O$_{19}$ (ASL) crystal along 〈100〉 direction was successfully grown using the Czochralski technique under azote atmosphere. Absorption and emission spectra of Pr:ASL crystal have been measured at room temperature. Continuous-wave laser operation of the a-cut and c-cut Pr:ASL samples under InGaN laser diode pumping has been demonstrated. For deep red laser operation at about 726 nm, the maximum output powers achieved from a-cut sample was 92.8 mW with slope efficiency of about 11.9%, while 46.6 mW with slope efficiency of 8.0% for the c-cut sample. For red laser at about 645 nm, maximum output powers of 49.2 mW and 42.8 mW were obtained for the a-cut sample and c-cut sample, corresponding to a slope efficiency of 6.7% and 8.5%, respectively.