title: Versatile large-mode-area femtosecond laser-written Tm:ZBLAN glass chip lasers.
abstract: We report performance characteristics of a thulium doped ZBLAN waveguide laser that supports the largest fundamental modes reported in a rare-earth doped planar waveguide laser (to the best of our knowledge). The high mode quality of waveguides up to 45 um diameter (~1075 μm(2) mode-field area) is validated by a measured beam quality of M(2)~1.1 ± 0.1. Benefits of these large mode-areas are demonstrated by achieving 1.9 kW peak-power output Q-switched pulses. The 1.89 μm free-running cw laser produces 205 mW and achieves a 67% internal slope efficiency corresponding to a quantum efficiency of 161%. The 9 mm long planar chip developed for concept demonstration is rapidly fabricated by single-step optical processing, contains 15 depressed-cladding waveguides, and can operate in semi-monolithic or external cavity laser configurations.
authors.affiliation: IPAS and School of Chemistry & Physics, University of Adelaide, South Australia, Australia. david.lancaster@adelaide.edu.au
authors.forename: D G
authors.initials: DG
authors.lastname: Lancaster
authors.forename: S
authors.initials: S
authors.lastname: Gross
authors.forename: A
authors.initials: A
authors.lastname: Fuerbach
authors.forename: H Ebendorff
authors.initials: HE
authors.lastname: Heidepriem
authors.forename: T M
authors.initials: TM
authors.lastname: Monro
authors.forename: M J
authors.initials: MJ
authors.lastname: Withford
mesh_terms: D000535:Aluminum / Q000737:chemistry; D001464:Barium / Q000737:chemistry; D004867:Equipment Design; D005459:Fluorides / Q000737:chemistry; D005898:Glass / Q000737:chemistry*; D007811:Lanthanum / Q000737:chemistry; D007834:Lasers; D008674:Metals, Rare Earth / Q000737:chemistry*; D012031:Refractometry / Q000379:methods*; D012964:Sodium / Q000737:chemistry; D013932:Thulium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry
chemical_list: D008674:Metals, Rare Earth; D001464:Barium; D007811:Lanthanum; D013932:Thulium; D012964:Sodium; D015040:Zirconium; D000535:Aluminum; D005459:Fluorides