Open AccessReal-time mode decomposition for few-mode fiber based on numerical method
Author(s) -
Liangjin Huang,
Shan Guo,
Jinyong Leng,
Hongliang Lü,
Pu Zhang,
Xin Cheng
Publication year - 2015
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.23.004620
Subject(s) - optics , modal , computer science , mode (computer interface) , laser , fiber laser , decomposition , laser beam quality , dynamic mode decomposition , materials science , physics , laser beams , polymer chemistry , operating system , ecology , machine learning , biology
Today a specific attention has been paid to look into the modal characteristics of the high-power laser beam. And the instantaneous monitoring and analyzing on modal content via the mode decomposition technique will provide a novel route. We implement the first-ever experimental investigation on the real-time mode decomposition technique for few-mode laser beam based on stochastic parallel gradient descent algorithm. It will reduce the cost and the complexity of the mode decomposition system. We have succeeded to decompose the mode spectra as well as calculating the beam quality factor at about 9 Hz monitoring rate, while the high agreement between the measured and reconstructed intensity profiles in each frame indicating the high accuracy and stability during the process. By employing a fiber-squeezing-based polarization controller, the modal content under test can be time-varying automatically.