Numerical analysis for structure optimization of seven-core photonic crystal fibers
七芯光子晶体光纤结构优化的数值分析

The eigenvalue equation associated with seven-core photonic crystal fiber was derived from coupled-mode equation. Mode properties were analyzed by its eigenvalues and eigenvector. Using the frequency domain finite difference method, the relationship between fiber structure and coupling coefficient was fully discussed through changing the wavelength, hole pitch and core distance. Mode shaping and higher-order supermode cut off was realized. The results were helpful to the fiber structure design and in-phase supermode selection.