Efficient 1.35 µm laser emission of Nd-doped Sr3Ga2Ge4O14 under in-band pumping with diode lasers

We describe the output performances of the 1.35 µm 4F3/2 → 4I13/2 transition in Nd‐doped Sr3Ga2Ge4O14 (SGG) under in‐band pumping with diode lasers at the 879 nm wavelength, directly into the 4F3/2 emitting level. An end‐pumped Nd:SGG crystal yielded 7.1 W of continuous‐wave (CW) output power for 17.7 W of absorbed pump power. The slope efficiency with respect to the absorbed pump power was 47.7%. To the best of our knowledge this is the first demonstration of such a laser system. Comparative results obtained for the pump with diode laser at 806 nm, into the highly‐absorbing 4F5/2 level, are given in order to prove the advantages of the in‐band pumping. (© 2011 by Astro Ltd., Published exclusively by WILEY‐VCH Verlag GmbH & Co. KGaA) (© 2011 by Astro Ltd., Published exclusively by WILEY‐VCH Verlag GmbH & Co. KGaA)