650-nm laser emission under upconversion pumping at 1.064 μm in Tm ~(+3): ZBLAN fiber laser

摘要

We report for the first time continuous wave (CW) red laser emission in Tm~(+3)-doped ZBLAN fiber laser, operated at 650 nm (~1 G _4 → ~3 F _4 transition of Tm~(+3)). The excitation uses a three step upconversion scheme. The pump source is a Nd:YAG laser operated at 1.064 μm. A laser output power of CW 80 mW was obtained for 1.42 W of launched pump power. The slope efficiency with respect to launched pump power was measured to be 7.7%. The temporal behavior of the emitted laser is also addressed.