Open Access219 kW narrow linewidth FBG-based MOPA configuration fiber laser
Author(s) -
Yusheng Huang,
Ping Yan,
Zehui Wang,
Jiemo Tian,
Dan Li,
Qirong Xiao,
Mali Gong
Publication year - 2019
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.003136
Subject(s) - laser linewidth , optics , materials science , fiber bragg grating , amplifier , fiber laser , laser , laser beam quality , laser power scaling , optoelectronics , physics , laser beams , cmos
In this paper, we demonstrated a monolithic fiber-Bragg-grating-based (FBG-based) master oscillator power amplification configuration fiber laser with a narrow linewidth at high-power level. Several approaches were implemented to reduce the seed laser linewidth and the magnification of spectrum broadening in order to achieve a narrow output linewidth. The narrow seed laser linewidth was obtained by restricting the reflection bandwidth of the FBG. To reduce the magnification of spectrum broadening, a backward pumping scheme was employed in the amplifier stage after its capacity to suppress laser spectrum broadening was preliminarily investigated experimentally. Further, by intentionally shortening the length of the active fiber in the amplifier and sharing the backward pumping power with the oscillator, the spectrum broadening was further inhibited without sacrificing optical efficiency. A maximum output power of 2.19 kW was achieved with a 3 dB spectrum bandwidth of only 86.5 pm. The beam quality at the maximum power was measured to be M 2 ~1.46. No sign of transverse mode instability was shown during the experiments.