Paper
21 February 2007 Characterization and stabilising dynamic phase fluctuations in large mode area fibres
Author Affiliations +
Abstract
Fibre amplifiers exhibit rapid time dependent phase fluctuations due to the environment and to thermal and other effects associated with the pumping and lasing processes. We characterise these effects in a large mode area fibre amplifier having an output power of 260W limited only by pump power. The amplifier retains its coherence even at the highest available output power with negligible linewidth broadening. Phase fluctuations are characterised by a low-amplitude power-independent jitter superimposed on a power-dependent drift due to heating. We also measure the phase fluctuations in a COTS fibre preamplifier and find they are predominantly large amplitude periodic oscillations at 110Hz, probably induced by pump power fluctuations. The two amplifiers were combined in series to give a high gain amplifier chain and actively phase stabilised to high precision (~&lgr;/37 rms) using a piezo-ceramic fibre stretcher incorporated into a PC-based feedback loop.
© (2007) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
D. C. Jones and A. M. Scott "Characterization and stabilising dynamic phase fluctuations in large mode area fibres", Proc. SPIE 6453, Fiber Lasers IV: Technology, Systems, and Applications, 64530Q (21 February 2007); https://doi.org/10.1117/12.717624
Lens.org Logo
CITATIONS
Cited by 2 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Amplifiers

Fiber amplifiers

Commercial off the shelf technology

Phase measurement

Feedback loops

High power fiber amplifiers

Phase shifts

Back to Top