横磁模式下二维非磁化等离子体光子晶体的线缺陷特性研究

Defect mode properties of two-dimensional unmagnetized plasma photonic crystals with line-defect under transverse magnetic mode

采用等离子体的分段线性电流密度卷积时域有限差分算法研究了横磁波入射时具有单一线缺陷的二维非磁化等离子体光子晶体的缺陷模特性.从频域角度分析得到微分高斯脉冲的透射系数,并讨论该光子晶体的晶格常数、介质圆柱半径、周期常数、缺陷层参数和等离子体参数对缺陷模特性的影响.结果表明,改变周期常数、缺陷层位置和等离子体碰撞频率不会改变缺陷模的频率,改变缺陷层介质圆柱的相对介电常数、半径和缺陷层到介质层的中心距离可以在不改变禁带宽度的前提下实现对缺陷模的调节,改变晶格常数、介质圆柱半径和等离子体频率能同时实现对禁带宽度和缺陷模的调节.

The piecewise linear current density recursive convolution finite-difference time-domain method of plasma is used to study the defect mode properties of transverse magnetic wave propagation in the two-dimensional unmagnetized plasma photonic crystals with a line-defect layer. In frequency domain,the transmission coefficients of electromagnetic differential Gaussian pulses are computed,and the effect of lattice constant,dielectric column radius,periodic constant,parameters of plasma and parameters of line-defect layer on defect mode properties of two-dimensional unmagnetized plasma photonic crystals are analyzed. The results illustrate that the frequency of defect mode cannot be tuned by changing periodic constant,position of the defect layer and plasma collision frequency,but be tuned by changing relative permittivity and radius of dielectric column in the defect layer,and central distance between defect layer and dielectric layer with the width of prohibit band gaps fixed. Furthermore,the defect mode and the width of prohibit band gaps can also be tuned by changing lattice constant,dielectric column radius and plasma frequency.