title: Highly efficient mid-infrared dysprosium fiber laser.
abstract: A new, highly efficient and power scalable pump scheme for 3 μm class fiber lasers is presented. Using the free-running 2.8 μm emission from an Er3+-doped fluoride fiber laser to directly excite the upper laser level of the H13/26→H15/26 transition of the Dy3+ion, output at 3.04 μm was produced with a record slope efficiency of 51%. Using comparatively long lengths of Dy3+-doped fluoride fiber, a maximum emission wavelength of 3.26 μm was measured.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Majewski
authors.forename: Stuart D
authors.initials: SD
authors.lastname: Jackson