title: Pump absorption and temperature distribution in erbium-doped double-clad fluoride-glass fibers.
abstract: We investigate diode pump absorption and temperature distribution in three erbium-doped double-clad fluoride fibers. Absorption is measured via fluorescence intensity and temperature distribution is measured with thermal imaging. Ray-tracing calculations of absorption and heat-equation modeling of temperature distribution are also conducted. We found excellent agreement between measurements and calculations for all fibers. Results indicate that erbium-doped fluoride fiber lasers have already reached maximum output powers allowed under natural convection cooling, with fiber end being the most critical. We propose cooling and fiber design optimizations that may allow an order-of-magnitude further power-scaling.
authors.affiliation: Laboratory for Quantum Optics, Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia.
authors.forename: Martin
authors.initials: M
authors.lastname: Gorjan
authors.forename: Marko
authors.initials: M
authors.lastname: Marincek
authors.forename: Martin
authors.initials: M
authors.lastname: Copic
mesh_terms: D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D004871:Erbium / Q000737:chemistry*; D005459:Fluorides / Q000737:chemistry*; D005898:Glass / Q000737:chemistry*; D054023:Lasers, Semiconductor; D055100:Optical Fibers; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013696:Temperature; D013814:Thermal Conductivity
chemical_list: D004871:Erbium; D005459:Fluorides