Open AccessSelf-inscribed antisymmetric long-period grating in a dual-core As_2Se_3-PMMA fiber
Author(s) -
Curtis L. Baker,
Song Gao,
Liang Chen,
Xiaoyi Bao
Publication year - 2017
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.25.012409
Subject(s) - optics , graded index fiber , materials science , core (optical fiber) , fiber bragg grating , long period fiber grating , grating , antisymmetric relation , dispersion shifted fiber , optical fiber , photonic crystal fiber , fiber optic sensor , physics , mathematical physics
We report for the first time that transmission of optical pulses centered at a wavelength of 1550 nm through a tapered dual-core As 2 Se 3 -PMMA fiber inscribes an antisymmetric long-period grating. The pulse power is equally divided between even and odd modes that superpose along the dual-core fiber to form an antisymmetric intensity distribution. A permanent refractive-index change that matches the antisymmetric intensity distribution is inscribed due to photosensitivity at the pulse central wavelength. The evolution of the transmission spectrum of the dual-core fiber is experimentally measured as the accumulated time that the fiber is exposed to the pulse is increased. A theoretical model of an antisymmetric long-period grating in a dual-core fiber computationally reproduces the experimentally observed evolution of the transmission spectrum. Experimental results indicate that antisymmetric long-period gratings induce effective group-velocity matching between the even and odd modes of the dual-core fiber, and reveal for the first time that long-period gratings can lead to slow light propagation velocities.