Open AccessSuperposing Multiple LP Modes With Microphase Difference Distributed Along Fiber to Generate OAM Mode
Author(s) -
Yangjin Li,
Long Jin,
Hang Wu,
Shecheng Gao,
Yuan-Hua Feng,
Zhaohui Li
Publication year - 2017
Publication title -
ieee photonics journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.725
H-Index - 73
eISSN - 1943-0655
pISSN - 1943-0647
DOI - 10.1109/jphot.2017.2674022
Subject(s) - engineered materials, dielectrics and plasmas , photonics and electrooptics
We propose a new method to generate orbital angular momentum (OAM) mode by superposing multiple LP11 modes with microphase difference distributed along fiber propagation. This way, OAM mode can be generated by superposing a series of LP11 mode with phase difference much less than π/2, which is necessary for schemes using two degenerated LP11 mode superposition but is difficult to generate and hard to keep stable. We demonstrate this principle experimentally by utilizing few-mode fiber long period grating (FMF-LPG), in which a series of LP11 modes with microphase difference distribution can be generated by twisting FMF-LPG. This scheme provides a potential all-fiber, compact, and low-attenuation scheme to generate stable OAM modes.