Title :
All-optical signal gating in cascaded long-period fiber gratings
Author :
Jeong, Yoonchan ; Baek, Seungin ; Lee, Byoungho
Author_Institution :
Sch. of Electr. Eng., Seoul Nat. Univ., South Korea
Abstract :
An all-optical signal gating has been demonstrated in cascaded long-period fiber gratings using cross-phase modulation by means of Q-switched pump wave packets. The obtained cascaded twin long-period fiber gratings showed an extremely narrow band of rejection of 0.5-nm bandwidth. Using this narrowband rejection filter, all-optical switching efficiency in long-period fiber grating devices could be enhanced so that they can be operated with relatively low pump intensities. Approximately a 20% modulation depth of a signal wave at 1565 nm was obtained with a pump intensity of 1 GW/cm/sup 2/ at 1064 nm. The experimental results are in good agreement with numerical expectations by the discretized coupled-mode theory, which was previously proposed for the nonlinear long-period fiber grating analysis.
Keywords :
Q-switching; diffraction gratings; optical communication equipment; optical fibre communication; optical information processing; optical modulation; optical pumping; phase modulation; 1064 nm; 1565 nm; Q-switched pump wave packets; all-optical signal gating; all-optical switching efficiency; cascaded long-period fiber gratings; cross-phase modulation; discretized coupled-mode theory; extremely narrow rejection band; long-period fiber grating devices; modulation depth; narrowband rejection filter; nonlinear long-period fiber grating analysis; pump intensity; relatively low pump intensities; twin long-period fiber gratings; Bragg gratings; Couplings; Fiber gratings; Filters; Narrowband; Optical fiber communication; Optical fiber devices; Optical fiber theory; Optical fibers; Permittivity;
Journal_Title :
Photonics Technology Letters, IEEE
