Coupling characteristics of dual-core photonic bandgap fibers with triangular photonic crystal cladding are investigated by use of a vector plane-wave expansion method and a vector finite-element method. We demonstrate the eigenmodes and the coupling length for two orthogonal polarizations. A decoupling phenomenon is found at a certain wavelength in this fiber configuration. The decoupling effect is attributed to the effect of surface modes on the eigenmodes. The decoupling wavelength decreases as the ratio of core radius to cladding air-hole pitch increases from 1.05 to 1.15.
© 2005 Optical Society of America
(060.0060) Fiber optics and optical communications : Fiber optics and optical communications
(060.1810) Fiber optics and optical communications : Buffers, couplers, routers, switches, and multiplexers
(060.2270) Fiber optics and optical communications : Fiber characterization
(060.2280) Fiber optics and optical communications : Fiber design and fabrication
Fiber Optics and Optical Communications
Zhi Wang, Guiyun Kai, Yange Liu, Jianfei Liu, Chunshu Zhang, Tingting Sun, Chao Wang, Weigang Zhang, Shuzhong Yuan, and Xiaoyi Dong, "Coupling and decoupling of dual-core photonic bandgap fibers," Opt. Lett. 30, 2542-2544 (2005)