title: Simultaneous spectrum and coherent combining by active phasing dual two-tone all-fiber MOPA chains.
abstract: We present a new approach for simultaneous spectral and coherent combining in a master oscillator power amplifier (MOPA) configuration with active phasing. Spectrally combined single-frequency seed lasers are employed as a master oscillator for the all-fiber power amplifier chain, which provides robust performance suppressing of the stimulated Brillouin scattering effect, while coherent combining of spectrally combined amplifiers with active phase control provides stable in-phase combining, despite the strong phase fluctuation. In experiments, two spectrally combined seed MOPA chains are coherently combined with a total output power of 390 W. The power of the main lobe in the closed loop is two times of that value in the open loop, and visibility of more than 75% of the long-exposure interference pattern at the receiving plane is obtained.
authors.affiliation: College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha, 410073, China.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Wang
authors.forename: Jingyong
authors.initials: J
authors.lastname: Leng
authors.forename: Hu
authors.initials: H
authors.lastname: Xiao
authors.forename: Yanxing
authors.initials: Y
authors.lastname: Ma
authors.forename: Pu
authors.initials: P
authors.lastname: Zhou
authors.forename: Wenbo
authors.initials: W
authors.lastname: Du
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Xu
authors.forename: Zejin
authors.initials: Z
authors.lastname: Liu
authors.forename: Yijun
authors.initials: Y
authors.lastname: Zhao