Yellow pumped Pr 3+ -doped ZBLAN fiber laser at 1015 nm.

To date, lasing in the visible to near-infrared wavelengths has been studied for praseodymium-doped fluoride fibers with the upper energy level of ³ P ₀ . In this Letter, a fiber laser operating at 1015 nm has been realized for the first time, to the best of our knowledge, which confirms a new mechanism where ¹ D ₂ can be the upper energy level. A maximum output power of 241 mW, with a slope efficiency of 30%, was achieved by using a 150-cm-long active fiber pumped at a maximum pump power of 823 mW. Furthermore, the broad emission spectra of Pr ³⁺ -doped fibers in the near-infrared band have been exploited as new, to the best of our knowledge, spectral sources.