拉锥光纤中光传输模场的矢量分析

采用二维矢量时域有限差分法(FDTD),考虑了拉锥光纤芯层的折射率分布和光纤芯层直径等参数,详细分析了拉锥光纤的锥度、拉锥后纳米光纤半径等对拉锥光纤中光波模场分布和传输特性的影响。计算结果表明,单模光纤芯层的折射率分布函数对光纤中光传输模场分布影响较小;拉锥光纤锥度越大光波的能量损耗越大;当拉锥后纳米光纤半径逐渐变小时,纳米光纤的光传输模场中心光强先逐渐增强然后又逐渐减小。

Vector analysis of transmission mode in tapered optical fiber

The effects of cone-shaped degree of taped fiber and radius of nanofiber etc.On distribution and transmission of optical field along taped fiber have been analyzed by using 2D vector finite-difference time-domain method(FDTD) and considering the refractive index distribution and the diameter of the core of the tapered optical fiber.The calculated results show that: the refractive index distribution in the core of single mode fiber has little influence on distribution of optical mode field transmitting in the fiber;larger the cone-shaped degree,higher the loss of optical energy;when the radius of the nanofiber after tapered region changes from large value to small value,the axile intensity of optical field transmitting in nanofiber increased firstly and then decreased gradually.