中文摘要：

设计了一种沿光纤轴向线性变化的锥形微结构光纤,该光纤在1.55μm波长处具有反常色散.利用自适应分步傅里叶方法求解非线性薛定谔方程,对中心波长为1.55μm、初始脉宽为1ps的脉冲在锥形微结构光纤中的传输进行了模拟,利用1m长的锥形微结构光纤实现了光脉冲的高效压缩,获得了压缩因子为56.9、品质因子为27的脉冲压缩效果.从脉冲在光纤中的演化发现,在反常色散区基于非线性渐增、色散渐减的锥形微结构光纤有利于实现脉冲的高效率压缩.与普通非线性光子晶体光纤相比,锥形微结构光纤粗端具有较大的有效模式面积,这有利于激光脉冲耦合进入光纤.

英文摘要：

A kind of linerly tapered microstructure fiber has been proposed in this paper.The central wavelength,which is located in the anomalous dispersion region,is 1550 nm.We use an adaptive split-step Fourier method to numerically study the propagation of 1 ps laser pulse in this microstructure optical fiber.For the tapered fiber under consideration,a compression factor of 56.9 and a quality factor of 27 can be achieved in a fiber 1 m long.With the pulse shape evolution in the fiber,we find that in anomalous dispersion region,the pulse can be highly efficiently compressed by the increasing of nonlinearity coefficient and the decreasing of dispersion coefficient.Compared with the normal photonic crystal fibers,the thicker end of the tapered fiber is apt to be coupled to the laser pulse which has a larger effective mode area.