Paper
12 March 2024 Mitigation of transverse mode instability by polarization rotation in high-power PM fiber amplifiers
Author Affiliations +
Abstract
We investigate Transverse Mode Instability (TMI) in an in-house large-mode-area Polarization Maintaining (PM) fiber amplifier. The TMI threshold was systematically measured at different linear polarization input angles with respect to the slow axis of the fiber. At a polarization input angle of 50°, the TMI threshold increased by more than 100% with respect to the threshold of the slow axis and 60% with respect to one of the fast axis. Furthermore, the temporal characteristic of TMI were studied in detail at different polarization input angles but fixed power of 290W, which was above the TMI threshold of the slow and fast axis. This analysis revealed the three different temporal regimes associated to TMI: chaotic fluctuations in the slow-axis, stable at 50°, and periodic fluctuations in the fast axis. These new results provide with valuable insights into the effect of TMI, especially concerning PM fibers, as well as with a relatively simple way of mitigating TMI in these fibers.
© (2024) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Gonzalo Palma-Vega, Denny Hässner, Stefan Kuhn, Johannes Nold, Friedrich Möller, César Jáuregui, Andreas Tünnermann, Jens Limpert, Nicoletta Haarlammert, and Thomas Schreiber "Mitigation of transverse mode instability by polarization rotation in high-power PM fiber amplifiers", Proc. SPIE 12865, Fiber Lasers XXI: Technology and Systems, 1286504 (12 March 2024); https://doi.org/10.1117/12.3001675
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Transverse mode instability

Polarization

Fiber amplifiers

Birefringence

Refractive index

Back to Top