Growth, spectroscopic properties and efficient laser action of an Yb0.09Lu0.13Gd0.78Ca4O(BO3)3 crystal

Abstract

A new Yb-ion laser crystal of Yb_0.09Lu_0.13Gd_0.78Ca₄O(BO₃)₃ was grown by using the Czochralski method. The polarized absorption and emission spectra with respect to the three principal optic axes were obtained, with the maximum cross-section of the zero-phonon absorption and emission determined to be 1.90 × 10⁻²⁰ cm² (E//X) and 1.55 × 10⁻²⁰ cm² (E//X), respectively. An analysis of gain curves indicates the superiority of this crystal to Yb:GdCOB in realizing laser operation at the zero-phonon line of around 977 nm. Efficient continuous-wave laser action was achieved in the main emission band, generating an output power of 13.53 W with an optical-to-optical efficiency of 64.6%, and the slope efficiency amounting to 71%.