Open AccessOptimizing high-power Yb-doped fiber amplifier systems in the presence of transverse mode instabilities
Author(s) -
César Jáuregui,
Hans-Jürgen Otto,
Sven Breitkopf,
Jens Limpert,
Andreas Tünnermann
Publication year - 2016
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.007879
Subject(s) - photodarkening , optics , amplifier , transverse plane , materials science , transverse mode , fiber , mode volume , core (optical fiber) , instability , optical fiber , optoelectronics , fiber laser , polarization maintaining optical fiber , physics , fiber optic sensor , mechanics , laser , composite material , cmos , structural engineering , engineering
The average output power of Yb-doped fiber amplifier systems is currently limited by the onset of transverse mode instabilities. Besides, it has been recently shown that the transverse mode instability threshold can be significantly reduced by the presence of photodarkening in the fiber. Therefore, reducing the photodarkening level of the core material composition is the most straightforward way to increase the output average power of fiber amplifier systems but, unfortunately, this is not always easy or possible. In this paper we present guidelines to optimize the output average power of fiber amplifiers affected by transverse mode instabilities and photodarkening. The guidelines derived from the simulations do not involve changes in the composition of the active material (except for its doping concentration), but can still lead to a significant increase of the transverse mode instability threshold. The dependence of this parameter on the active ion concentration and the core conformation, among others, will be studied and discussed.