Spectral properties and 1.5–1.6 μm laser operation of Er:Yb:NaCe(WO4)2 crystal

An Er:Yb:NaCe(WO 4 ) 2 crystal was grown by the Czochralski method. Spectral properties of the crystal were investigated and compared with those of the Er:Yb:Ce:NaGd(WO 4 ) 2 crystal. The green up-conversion was not observed when the Er:Yb:NaCe(WO 4 ) 2 crystal was excited by a diode laser at 970 nm. The efficiency of energy transfer from Yb 3+ to Er 3+ in the Er:Yb:NaCe(WO 4 ) 2 crystal was calculated to be about 93%. End-pumped by a diode laser at 970 nm in a hemispherical cavity, 0.95 W quasi-CW laser at 1.5–1.6 μm was achieved in a 1.47-mm-thick c -cut Er:Yb:NaCe(WO 4 ){ia2} crystal, the slope efficiency was 11%, and the threshold was 2.83 W.