Luminescent and laser properties of Yb–Er:GdCa4O(BO3)3: a new crystal for eye-safe 1.5-μm lasers

We present for the first time 1.5-μm laser emission in Yb–Er:GdCa4O(BO3)3 (GdCOB). The crystals were grown by the Czochralski method from platinum crucibles. Spectroscopic and laser tests of the crystals are described. A continuous-wave output power of 80 mW was achieved in a monolithic microchip cavity under laser-diode pumping.