title: High-power Tm-doped fiber distributed-feedback laser at 1943 nm.
abstract: We report on high-power operation of a fiber distributed-feedback (DFB) laser fabricated from Tm-doped photosensitive alumino-silicate fiber and in-band pumped by an Er/Yb fiber laser at 1565 nm. The fiber DFB laser yielded up to 875 mW of single-ended output at 1943 nm on two orthogonally polarized modes for 3.5 W of absorbed pump power. Further scaling of the DFB laser output power was achieved with the aid of a simple Tm-doped fiber amplifier stage spliced directly to the DFB fiber without the need of an optical isolator. The maximum output power from the DFB laser and fiber amplifier was >3 W for a combined absorbed pump power of 8.1 W. The influence of thermal loading, owing to quantum defect heating in the Tm-doped core, on the output power and longitudinal mode behavior is discussed, and the prospects for further improvement in performance are considered.
authors.affiliation: Optoelectronics Research Centre, University of Southampton, Southampton, UK. zhz@orc.soton.ac.uk
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
authors.forename: D Y
authors.initials: DY
authors.lastname: Shen
authors.forename: A J
authors.initials: AJ
authors.lastname: Boyland
authors.forename: J K
authors.initials: JK
authors.lastname: Sahu
authors.forename: W A
authors.initials: WA
authors.lastname: Clarkson
authors.forename: M
authors.initials: M
authors.lastname: Ibsen