Efficient 2.96 μm dysprosium-doped fluoride fibre laser pumped with a Nd:YAG laser operating at 1.3 μm

A quasi-continuous wave Dy3+-doped ZBLAN fibre laser pumped by a similar to 1.3 mu m Nd:YAG laser and operating at 2.96 mu m with an emission linewidth of similar to 14 nm (FWHM) has been demonstrated. The H-6(15/2) -> H-6(9/2), F-6(11/2) absorption band of Dy3+-doped ZBLAN centred at 1.3 mu m has been used to pump the H-6(13/2) -> H-6(15/2) laser transition. For a 60 cm fibre length, a threshold of 0.5 W and a slope efficiency of similar to 20% with respect to the absorbed pump power was measured. The experimental slope efficiency was similar to 45% of the Stokes efficiency limit. The high efficiency relates to low pump ESA losses and an optimised output coupling as compared with previous demonstrations. (c) 2006 Optical Society of America.