4.3 μm低损耗硫系空芯光子带隙光纤结构设计及性能研究

The band-gap maps of As2S3,Ge20Se65Sb15 and As2Se3 chalcogenide glass fibers at different airfillings were analyzed by using the plane wave expansion method,.The results show that when increased to 0.75,the photonic band gap and air lines have appeared intersection mode,the band gap is wide,and an appropriate laser transmission mode in the core of fiber is formed.Under different fiber core diameter,using the finite element method,the fundamental mode confinement loss and effective mode area of homemade Ge20Se65Sb15 chalcogenide glass hollow-core photonic crystal fiber were systematically studied.The results show that the confinement loss is the lowest and the effective mode-field area is very small when the core diameter is 9.2μm.By optimizing the structural parameters of fiber,a hollow-core photonic crystal fiber with low confinement loss(0.00472dB/m)and effective mode-field area(58.046μm2)at 4.3μm was obtained.