Research On The Negative Refraction Phenomenon Of Two-dimensional Triangular Lattice Layer-by-layer Photonic Crystal

The negative refraction effect of the photonic crystal can make the electromagnetic wave band of negative refraction expand from the microwave section to the light band.This will have a profound impact on optical storage,photolithography,and other micromachining technologies in ultra large scale integrated circuits.In this paper,we propose a two-dimensional(2-D)triangular lattice close-packed photonic crystal plate.The phenomena and characteristics of the negative refraction of the two-dimensional photonic crystal medium plate are studied.The main contents and conclusions of this paper are as follows:(1)The concept of photonic crystal and the two important properties of photonic crystal,photonic band gap and photon local domain are introduced.Two commonly used methods of calculation of photonic crystal-plane wave expansion and finite time difference time difference method and two basic ways of realizing negative refraction in photonic crystals are described in detail.And the research progress associated with negative refraction photonic crystal is surveyed.Finally,details of the practical application of photonic crystal negative refraction.(2)We designed a 2-D triangular lattice photonic crystal plate.The equal frequency diagram of the band and the first Brillouin zone is analyzed by the plane wave expansion method(PWE),and the reason why the photonic crystal can observe the negative refraction is explained.The imaging characteristics of the negative refraction of the point light source in the photonic crystal plate lens are numerically simulated by the finite difference time domain(FDTD)method.Clear image spots of a point source with normalized frequency ?=0.3605(2?c/a)vertical incident media plate are obtained in the image plane.The 2-D triangular lattice photonic crystal plate lens realizes "perfect imaging".Similarly,the analysis method is used to simulate different arrangements and different lattice types.Negative refraction can be observed under the incident light source at the corresponding frequency,but the perfect point source cannot be achieved at image plane.(3)A two-dimensional triangular lattice photonic crystal with dense stacked structure is designed.With the plane wave expansion method to set the size of the scattering cylindrical different refractive index can be simulated with the first Brillouin zone and frequency map,find the refraction theory can produce perfect imaging rate;then with the observation and analysis of the finite difference time domain method of negative refraction phenomenon.