Laser oscillation in yellow and blue spectral range in Dy/sup 3+/:ZBLAN

Summary form only given. Compact and efficient all solid-state lasers emitting several ten to hundred milliwatts in the visible spectral region are of great interest for widespread applications in medicine, biology, metrology, optical storage and display technology. Usually, air-cooled argon ion lasers or frequency-doubled solid-state lasers are employed for these purposes. Upconversion fiber lasers in fluoride glasses offer an alternative, in which direct laser emission in the visible spectral range is possible without applying nonlinear parametric processes. However, these reported lasers do not cover the entire visible spectral range. We report on excited state absorption spectroscopy in several rare-earth ions in fluorozirconate host glass and discuss the possibility of upconversion. pump processes in order to access a number of visible laser transitions. As a result CW laser emission in a dysprosium-doped ZBLAN fiber at 575 nm and 478 nm is realized for the first time.