Opt Lett. 2018 May 15;43(10):2360-2363. doi: 10.1364/OL.43.002360.
We calculated the out-of-plane band structure of a two-dimensional dispersive photonic crystal (PC). To achieve this goal, the plane wave expansion method was implemented in conjunction with a numerical algorithm, the dispersive photonic crystal iterative method. The PC is an array of circular cross-sectional dispersive MgO Lorentz single-pole rods in a square lattice. The frequency bands are calculated starting at Γ as a function of the oblique component of the wave vector. For the lowest frequencies, it was found that the modes bend drastically to the horizon as the dielectric constant ϵ(ω) is increased to a very positive value. For frequencies above the longitudinal optical phonon circular frequency, where ϵ(ω) has very low positive values, the expected degeneration occurs in the transparency window, and a line of modes behaves close to the line of light.
我们计算了二维色散光子晶体（PC）的面外能带结构。为了实现这一目标，我们采用了平面波展开法，并结合了数值算法，即色散光子晶体迭代法。PC 是由在正方形晶格中排列的圆形横截面弥散 MgO 洛伦兹单极棒组成。从 Γ 点开始，作为波矢的斜分量的函数，计算了频带。对于最低频率，当介电常数 ϵ(ω)增加到非常正值时，发现模式急剧弯曲到水平方向。对于高于纵向光学声子圆频率的频率，其中 ϵ(ω)具有非常小的正值，在透明窗口中发生了预期的简并，并且一系列模式的行为接近于光线。
