Upconversion fluorescence and laser emission in the visible under Ti:sapphire laser pumping at 800 nm in the ZBLAN:Er3+ optical fiber

Infrared-to-visible upconversion in rare-earth doped optical fibers is a very interesting phenome-non, but its application in building a practically useful laser requires much more experimental work. In this paper, infrared-to-visible upconversion fluorescence observed perpendicularly to the fiber and laser emission in ZBLAN:Er3+ fiber under 800 nm excitation from a Ti:sapphire laser are described. Absorption at the pump wavelength, threshold power pumping density, and output power dependence vs. fiber length have been measured. The output power in the green (544 nm) amounts to 22 mW. Important technical details of the experiment are described.