The numerical study on the performance of large-mode-area (LMA) fibers coiled onto a spool in high power amplifier is carried out as the bend-induced distortion of fiber modes severely affects the output characteristics of amplifier systems. The variations for high-order mode bend distortion with different orientations relative to the plane of the fiber bend are observed and shown. Concerning the practical applications, a bend-resistant LMA fiber with the mode area larger than 1000 \mum2 and excellent high-order mode suppression is designed completely by optimizing the refractive index (RI) and dopant profile. The results indicate that a hybrid profile of RI and dopant is the best choice for LMA fiber with coiling.
© 2009 Chinese Optics Letters
(060.2280) Fiber optics and optical communications : Fiber design and fabrication
(060.2320) Fiber optics and optical communications : Fiber optics amplifiers and oscillators
(140.3510) Lasers and laser optics : Lasers, fiber
Shuang Chen, Ying Feng, and Ling Wang, "Design of large-mode-area rare earth doped fiber for high power coiled fiber amplifier," Chin. Opt. Lett. 7, 671-674 (2009)