摘要
We numerically investigate the mode exciting properties of photonic crystal fibres by using the beam propagation method when the optical field is input from a traditional single mode fibre. The results show that both the excited mode spectrum and the coupling-efficiency of each excited mode depend on the normalized pitch А/λ and the normalized hole-size А/λ. Furthermore, we obtain the boundary profile of the optimizing coupling-efficiency for the excited fundamental mode： the boundary （А/λ）＊ is linear to the boundary （А/λ）. All of these will pave the way for smoothing applications of photonic-crystal fibres, such as splicing and designing photonic-crystal-fibre functional devices.
We numerically investigate the mode exciting properties of photonic crystal fibres by using the beam propagation method when the optical field is input from a traditional single mode fibre. The results show that both the excited mode spectrum and the coupling-efficiency of each excited mode depend on the normalized pitch А/λ and the normalized hole-size А/λ. Furthermore, we obtain the boundary profile of the optimizing coupling-efficiency for the excited fundamental mode： the boundary （А/λ）＊ is linear to the boundary （А/λ）. All of these will pave the way for smoothing applications of photonic-crystal fibres, such as splicing and designing photonic-crystal-fibre functional devices.
基金
Supported by the National Basic Research Program of China under Grant No 2003CB314906, and the National Natural Science Foundation of China under Grant No 60577018.
