High efficiency Yb3+-doped phosphate single-mode fibre laser

Franczyk M., Stępień R., Piechal B., Pysz D., Stawicki K., Siwicki B. and Buczyński R.

Laser Physics Letters

14, 2017, art. 105102, 10.1088/1612-202X/aa7d39

We report on a ytterbium-doped phosphate glass single-mode fibre laser, 4 cm long, with a maximum output power of 11.6 W and a slope efficiency of 66.6%. We developed the double-clad fibre with a 19 µm diameter step-index core and a pump waveguide with a high numerical aperture due to external air-cladding. The estimated pump absorption in the fibre exceeded 700 dB m−1.