TUNABLE CW LASING AROUND 610, 635, 695, 715, 885 AND 910NM IN PRASEODYMIUM-DOPED FLUOROZIRCONATE FIBER

CW lasing operation of a praseodymium-doped fluorozirconate fibre laser at 610, 635, 695, 715, 885, 910 nm is reported, together with large tunability domains around these wavelengths. Output powers in excess of 20 mW at 610 nm, 50 mW at 715 nm and 100 mW at 635 nm with a photon efficiency larger than 50% have been obtained.