title: Watt-level ~2 μm laser output in Tm3+-doped tungsten tellurite glass double-cladding fiber.
abstract: We report, for the first time to the best of our knowledge, a watt level cw fiber laser at ~2 μm from a piece of 40-cm-long newly developed highly thulium-doped (3.76 × 10(20) ions/cm(3)) tungsten tellurite glass double cladding fiber pumped by a commercial 800 nm laser diode. The maximum output power of the fiber laser reaches 1.12 W. The slope efficiency and the optical-optical efficiency with respect to the absorbed pump are 20% and 16%, respectively. The lasing threshold is 1.46 W, and the lasing wavelength is centered at 1937 nm.
authors.affiliation: Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China. kfli@siom.ac.cn
authors.forename: Kefeng
authors.initials: K
authors.lastname: Li
authors.forename: Guang
authors.initials: G
authors.lastname: Zhang
authors.forename: Lili
authors.initials: L
authors.lastname: Hu