Coupling characteristics of dual-core photonic crystal fiber couplers.

Coupling characteristics of dual-core photonic crystal fiber (PCF) couplers are evaluated by using a vector finite element method and their application to a multiplexer-demultiplexer (MUX-DEMUX) based on PCF is investigated. The PCF couplers for 1.48/1.55-m, 1.3/1.55-m, 0.98/1.55-m, and 0.85/1.55-m wavelength MUX-DEMUX are designed and the beam propagation analysis of the proposed PCF couplers is performed. It is shown from numerical results that it is possible to realize significantly shorter MUX-DEMUX PCFs, compared to conventional optical fiber couplers.