title: Thermo-optical effects in high-power ytterbium-doped fiber amplifiers.
abstract: We investigate the effect of temperature gradients in high-power Yb-doped fiber amplifiers by a numerical beam propagation model, which takes thermal effects into account in a self-consistent way. The thermally induced change in the refractive index of the fiber leads to a thermal lensing effect, which decreases the effective mode area. Furthermore, it is demonstrated that the thermal lensing effect may lead to effective multi-mode behavior, even in single-mode designs, which could possibly lead to degradation of the output beam quality.
authors: Department of Photonics Engineering, Technical University of Denmark Bldg. 345v, DK-2800 Kgs. Lyngby, Denmark. kryh@fotonik.dtu.dk
authors: Kristian Rymann
authors: KR
authors: Hansen
authors: Thomas Tanggaard
authors: TT
authors: Alkeskjold
authors: Jes
authors: J
authors: Broeng
authors: Jesper
authors: J
authors: Lægsgaard
mesh_terms: D000669:Amplifiers, Electronic; D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005336:Fiber Optic Technology / Q000295:instrumentation*; D008027:Light; D008962:Models, Theoretical; D013696:Temperature; D015018:Ytterbium / Q000737:chemistry*
chemical_list: D015018:Ytterbium