Tunable 1 Micron Fiber Laser

In this Phase I study, we will demonstrate high power, continuous wave (CW) single spatial mode laser action at the 1 um wavelength. There are two innovative aspects in our proposal: the incorporation of commercially available very high power, not necessarily single mode, semiconductor laser diodes as pump sources; and, a novel single mode fiber, doped with the appropriate rare earth ions. The pump power can be efficiently coupled into and absorbed by the specially coated fiber. This approach is being tried here for the first time. The greatest advantage of our high power fiber laser product will be its enhanced mechanical stability compared to the solid state lasers, which use bulk optical components. Compared with other double clad fiber lasers which use thin films deposited at fiber ends as mirrors, our fiber lasers with Bragg fiber filters are highly resistant to thermal damage. Also, the fiber laser products will be easier to integrate with optical fiber delivery systems than other double clad lasers, and lasers which use crystal based hosts as the gain medium. The one micron fiber lasers have potential applications as superfluorescent sources, and in sensors and lidar. The tunable laser is particularly attractive for spectroscopic applications. These high power and high spectral resolution lasers can be used as sources for high-accuracy measurements of atmospheric aerosols from ground-based, aircraft and space-craft platforms.