Diode pumped visible Dy<sup>3+</sup>-doped silica fiber laser: Ge-co-doping effects on lasing efficiency and photodarkening
Tomoya Okazaki, Chiaki Otsuka, Edson H. Sekiya, Kota Kawai, Masato Mizusaki, Yuta Kanbayashi, Kazuya Saito
Abstract
Abstract We present the first demonstration of visible laser oscillation in the Dy 3+ -doped silica fiber pumped by a 451 nm InGaN laser diode. It was found that Ge-co-doping plays the following important roles of laser oscillation: (1) to reduce the Rayleigh scattering loss, (2) to suppress the X-ray-induced and pump-induced photodarkening (PD), and (3) to increase lasing slope efficiency. In a fiber with 0.46 wt% Dy, 1.8 wt% Ge, and 0.54 wt% Al, the slope efficiency is 22.0% at 582.5 nm, and the maximum output power is 18.4 mW.
Topics & Concepts
PhotodarkeningLasing thresholdSlope efficiencyMaterials scienceDopingOptoelectronicsSilica fiberLaserDiodeFiber laserLaser diodeOpticsFiberRayleigh scatteringWavelengthPhysicsComposite materialSolid State Laser TechnologiesPhotonic Crystal and Fiber OpticsAdvanced Fiber Laser Technologies