摘要：为了提高光子晶体光纤的非线性系数,降低色散斜率和制作难度,提出了一种硅纳米纤芯光子晶体光纤,其纤芯和包层空气孔都为圆形。利用平面波展开法进行仿真,研究了硅纳米纤芯直径、包层空气孔直径、晶格常数三个参量分别对色散和非线性系数的影响。通过优化,最终得到零色散波长在1550 nm处,具有高非线性、低色散斜率的光子晶体光纤。1550 nm处光纤的色散斜率低至0.251 ps·nm^(-2)·km^(-1),非线性系数高达1.0×10^(5)W^(-1)·km^(-1),限制损耗为0.39 dB/km。此外,该光纤结构简单、制作方便,在较小的工艺误差下仍能保持较好的性能。

摘要：提出了利用掺氟同心圆环的光纤结构来提高光子晶体光纤(PCF)的非线性,所需控制的参量仅有两个。设计了三种具有高非线性、低色散斜率和低限制损耗的全固光子晶体光纤。这三种光纤分别具有正常色散、双零色散点和零色散点恰好在1.55μm波长处的色散曲线特性。所设计的零色散点恰好在1.55μm波长处的光子晶体光纤色散斜率值为5.12×10-4 ps/(km·nm2),这比传统的高非线性光纤的色散斜率小了2个数量级。同时,该光纤在1.55μm波长处的非线性系数为31.5W-1·km-1,限制损耗为9.62×10-5 dB/km。

摘要：利用双光纤准直器研制出一种基于微电机械系统(M icro E lectron ic M echan ica l System,M EM S)技术的连续可调光衰减器,利用双光纤准直器光纤头(P igta il)的楔角面对C-L ens准直透镜产生的色散进行了补偿,使得该衰减器工作在C-B and及衰减范围内具有极低的波长相关损耗(W ave lengthD ependen t Loss,W DL)值.分析了影响该衰减器的其它光学性能的各个因素.对所试制样品进行测试结果表明:该衰减器具有良好的光学性能,插损(Insertion Loss,IL),回损(R eturn Loss,RL)等指标达到理想的结果,特别是W DL指标性能优于同类产品.

摘要：提出在三元复合宽带波片设计中,采用遗传算法在特定入射光频率范围内对复合波片系统的相位延迟误差和等效快轴方向夹角误差进行全局优化,并采用蒙特卡洛方法,通过程序仿真分析在晶体加工过程中尺寸公差对消色差性能的影响。结果表明,设计出的红外复合宽带波片在晶体厚度和方位角公差分别为1μm和0．5°时具有很好的消色差性能。

摘要：A simple design procedure is used to generate photonic crystal fibers （PCFs） with ultra-flattened chromatic dispersion. Only four parameters are required, which not only considerably saves the computing time, but also distinctly reduces the air-hole quantity. The influence of the air-hole diameters of each ring of hexagonal PCFs （H-PCF, including 1-hole-missing and 7-hole-missing H-PCFs）, circular PCFs （C-PCF）, square PCFs （S-PCF）, and octagonal PCFs （O-PCF） is investigated through simulations. Results show that regardless of the cross section structures of the PCFs, the 1st ring air-hole diameter has the greatest influence on the dispersion curve followed by that of the 2nd ring. The 3rd ring diameter only affects the dispersion curve within longer wavelengths, whereas the 4th and 5th rings have almost no influence on the dispersion curve. The hole-to-hole pitch between rings changes the dispersion curve as a whole. Based on the simulation results, a procedure is proposed to design PCFs with ultra-flattened dispersion. Through the adjustment of air-hole diameters of the inner three rings and hole-to-hole pitch, a flattened dispersion of 0±0.5 ps/（nm·km） within a wavelength range of 1.239 – 2.083 μm for 5-ring 1-hole-missing H-PCF, 1.248 – 1.992 μm for 5-ring C-PCF, 1.237 – 2.21 μm for 5-ring S-PCF, 1.149 – 1.926 μm for 5-ring O-PCF, and 1.294 – 1.663 μm for 7-hole-missing H-PCF is achieved.