Abstract

We report what we believe to be the first single-wavelength pumped, CW, room-temperature, blue upconversion laser. This 480 nm laser utilizes Tm³⁺ as the active ion in a fluoride glass host. Blue upconversion fiber lasers have already been demonstrated in both Pr³⁺-doped¹ and Tm³⁺ -doped² ZBLAN fibers. For Pr³⁺, CW, room-temperature operation at 490 nm was obtained, but required pumping with two separate, widely spaced infrared wavelengths. For Tm³⁺, CW operation also required two separate input wavelengths, in the red spectral region, as well as operation at 77 K. Recently room-temperature, pulsed operation of a bulk-crystal, blue upconversion laser has been reported in Tm³⁺-doped BaY_1.0Yb_0.99F₈.³

© 1992 Optical Society of America