高非线性高双折射光子晶体光纤的特性研究

Investigation of photonic crystal fibers with high nonlinearity and large birefringence

设计了一种新型结构的光子晶体光纤,在其包层和纤芯位置分别引入6个大空气孔和6个小空气孔,采用有限元法研究了该光纤的双折射、有效模面积、非线性系数和色散特性。数值计算结果表明,当光纤包层孔间距为1.0μm时,在1.55μm波长处获得了2.60×10-2的高双折射,在x、y偏振方向分别获得了39.08 W-1·km-1和47.53 W-1·km-1的高非线性系数,且该光纤的零色散波长位于近红外波段。这种高非线性高双折射光子晶体光纤在非线性光学、偏振控制和超连续谱产生方面具有广泛的应用前景。

A kind of highly nonlinear and large birefringence photonic crystal fiber is proposed. Six big air holes and six small air holes are added in the cladding and the fiber core respectively. Characteristics such as the birefringenee, effective mode area, nonlinear coefficient and dispersion of the fiber are investigated by the finite element method. Simulation results show that the birefringence reaches up to 2.60×10^2 at the wavelength of 1.55μm when the air hole pitch is1.0μm; the nonlinear coefficient is 39.08 W^-1.km^-1and 47.53 W^-1-km^-1 in x and y polarization directions respectively. In addition, this fiber has zero dispersion wavelengths in the infrared band and it could be widely used in the nonlinear optics, polarization control and super-continuum generation.