Open Access532 nm pump induced photo-darkening inhibition and photo-bleaching in high power Yb-doped fiber amplifiers
Author(s) -
Ruiting Cao,
Xianfeng Lin,
Yisha Chen,
Yongshi Cheng,
Yibo Wang,
Yingbin Xing,
Haiqing Li,
Lüyun Yang,
Gui Chen,
Jinyan Li
Publication year - 2019
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.27.026523
Subject(s) - materials science , optics , fiber laser , cladding (metalworking) , fiber , optical fiber , optoelectronics , laser , fiber amplifier , doping , double clad fiber , amplifier , irradiation , dispersion shifted fiber , fiber optic sensor , composite material , physics , nuclear physics , cmos
A novel method for mitigating photo-darkening and the effective photo-bleaching phenomenon by 532 nm cladding pump in Yb-doped fiber were herein reported. Compared with the pristine fiber, beyond 30% of photo-darkening induced excess loss was suppressed by 532 nm pretreatment. Moreover, the excess loss in the photo-darkened fiber was completely bleached with 532 nm pump. Additionally, the bleached fiber exhibited better photo-darkening resistance. Therefore, for high power application, a 20/400 gamma irradiated fiber was bleached in situ by 532 nm pump and the laser properties were explored. The output power restored to 421W accounting for 82% of the pristine fiber, with the mode instability threshold rising to over 2.6 times and the efficiency increasing from 37% to 63%. The results indicate 532 nm pump has bright prospects for the stable operation of high power fiber lasers.