论文部分内容阅读
设计出一种新型的渐变空气孔径THz波超平坦色散光子晶体光纤.应用时域有限差分方法(finite-difference time-domain,FDTD)计算光纤色散,所得结果表明渐变空气孔径光子晶体光纤比孔直径不变光子晶体光纤控制色散的能力更强;且当第三层与第四层空气孔直径相同时,孔直径渐变的光子晶体光纤的色散更趋于平坦,而当空气孔直径取d1=0.85d4,d2=0.95d4,d3=d4(d1,d2,d3,d4分别为包层从内到外空气孔的直径)时,此种光子晶体光纤可以在波长60—65μm(4.61—5THz)范围内将波导色散值控制在-0.1±0.3ps/(km·nm)范围内,得到趋于超平坦色散的、具有很好的束缚THz波的能力和良好的损耗特性的新型THz波光子晶体光纤.
A new type of THz-wave super-flattened dispersion photonic crystal fiber with a gradient air-aperture was designed.The fiber dispersion was calculated by finite-difference time-domain (FDTD) method.The results show that the ratio of aperture diameter The invariant photonic crystal fiber is more capable of controlling dispersion. When the diameters of the third and fourth air holes are the same, the chromatic dispersion of the photonic crystal fiber with the gradually-changing hole diameter tends to be flattened. When the air hole diameter takes d1 = 0.85 d4, d2 = 0.95d4, d3 = d4 (d1, d2, d3 and d4 are the diameters of the air holes in the cladding from the inside to the outside, respectively). Such a photonic crystal fiber can be used in the range of 60-65μm The waveguide dispersion value is controlled within the range of -0.1 ± 0.3ps / (km · nm) to obtain a new type of THz photonic crystal fiber with ultra-flattened dispersion, good THz-bound capability and good loss characteristics .