Numerical analysis of pump propagation and absorption in specially tailored double-clad rare-earth doped fiber

0449022 - ÚFE 2016 RIV US eng J - Journal Article
Koška, Pavel - Peterka, Pavel
Numerical analysis of pump propagation and absorption in specially tailored double-clad rare-earth doped fiber.
Optical and Quantum Electronics. Roč. 47, č. 9 (2015), s. 3181-3191. ISSN 0306-8919. E-ISSN 1572-817X
R&D Projects: GA ČR GA14-35256S
Grant - others:GA AV ČR(CZ) M100761202
Institutional support: RVO:67985882
Keywords : Finite element method * Fiber lasers * Double clad fibers
Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering
Impact factor: 1.290, year: 2015

We present a numerical analysis of multi-mode pump absorption in recently proposed double-clad fiber with stadium-like cross section of the inner cladding and asymmetrically placed rare-earth doped core. Such a cross section allows easy splicing of the multi-mode pump fiber and single-mode signal fiber to the double-clad fiber. The full-vector finite element beam propagation method was used as a numerical tool. In order to allow excitation of the structure by arbitrary field profile, definite set of functionals satisfying unisolvence condition together with hybrid edge-nodal finite element basis was derived. The flat-top field profile and more realistic speckle pattern were considered in the analysis. The effect of coiling and simultaneous twisting of the fiber was taken into account. It was found that the twisting of the DC fiber significantly improves the pump absorption
Permanent Link: http://hdl.handle.net/11104/0250604