The characteristics of the performance of a diode-cladding-pumped Yb<sup>3+</sup>, Ho<sup>3+</sup>-doped silica fiber laser are presented. To our knowledge this is the first demonstration of a Yb<sup>3+</sup>, Ho<sup>3+</sup>-doped fiber laser, and a maximum output power of 0.85 W was achieved for a launched pump power of 10.9 W. For launched pump powers <7 W, the slope efficiency was ∼12.5%. Visible fluorescence emission with peaks at ∼485, ∼550, and ∼660 nm measured at the output from the laser suggests that excited-state absorption and energy-transfer upconversion losses may impair the functioning of the laser. Increasing the Yb<sup>3+</sup> and Ho<sup>3+</sup> concentrations and the Yb<sup>3+</sup>:Ho<sup>3+</sup> concentration ratio may lead to an improvement in the overall efficiency of the device.
© 2003 Optical Society of America
(140.3070) Lasers and laser optics : Infrared and far-infrared lasers
(140.3480) Lasers and laser optics : Lasers, diode-pumped
(140.3510) Lasers and laser optics : Lasers, fiber
(140.3580) Lasers and laser optics : Lasers, solid-state
Stuart D. Jackson and Simon Mossman, "Diode-Cladding-Pumped Yb3+, Ho3+-Doped Silica Fiber Laser Operating at 2.1-μm," Appl. Opt. 42, 3546-3549 (2003)