Title :
Electrically controllable long-period liquid crystal fiber gratings
Author :
Yoonchan Jeong ; Byungchoon Yang ; Byoungho Lee ; Hong Seok Seo ; Sangsoo Choi ; Kyunghwan Oh
Author_Institution :
Sch. of Electr. Eng., Seoul Nat. Univ., South Korea
fDate :
5/1/2000 12:00:00 AM
Abstract :
An electrically controllable fiber-optic filter for broad-band rejection has been demonstrated by periodically poling a liquid-crystalline core in a hollow-core fiber by means of an external long-period-combed electrode. The periodically poled liquid-crystalline core in a period of 483 μm couples the fundamental core mode to the leaky cladding modes. A maximum loss dip of approximately 15-nm bandwidth and 6 dB band rejection has been obtained for a nonpolarized light with a combed 250-V external voltage modulation. The experimental result matches well with a numerical expectation, which has been analyzed by the discretized coupled-mode theory for an anisotropic perturbation.
Keywords :
coupled mode analysis; diffraction gratings; electro-optical filters; liquid crystal devices; optical fibre filters; 250 V; anisotropic perturbation; broad-band rejection; combed electrode; coupled mode theory; electrical control; fiber optic filter; fundamental core mode; leaky cladding mode; long-period liquid crystal fiber grating; loss dip; numerical discretization; Communication system control; Electrodes; Fiber gratings; Liquid crystals; Optical fiber communication; Optical fiber devices; Optical fiber filters; Optical fiber theory; Optical fibers; Optical refraction;
Journal_Title :
Photonics Technology Letters, IEEE