含单负材料的光子晶体的缺陷模和透射谱

Defect Mode and Transmission Spectrum of One-dimensional Photonic Crystals Containing Single-negative Materials

用传输矩阵法分析了由2类单负材料组成的含缺陷一维光子晶体的缺陷模及透射谱。结果表明:当缺陷为一层单负材料时,零有效相位带隙中出现2个缺陷模,且缺陷模的频率可通过缺陷层的厚度和2种单负材料的厚度比来调节。当缺陷为1组单负磁导率材料和单负介电材料组成的双缺陷时,通过选取合适的参数满足平均磁导率和平均介电常数都为零时,带隙中未出现缺陷模,而且带宽保持不变,带边电场也随着双缺陷厚度的增加而被强烈的局域。

The defect mode and transmission spectrum are analyzed by means of transfer-matrix method in one-dimensional photonic crystals composed of alternating layers of negative-permittivity material and negative-permeability material. The results show that：When the defect layer is one kind of single-negative material,two defect modes are found in the zero effective phase gap and can be tuned by varying the thickness of the defect layer or the thickness ratio of the two kinds of singlenegative materials. When the defect layers are two defects containing negative-permittivity material and negative-permeability material, we select appropriate parameters satisfying zero average permittivity and permeability conditions, there are no defect modes in the forbidden gap, and the gap width is invariant. With the increase of the size of the defect layers,the electric fields at high gap-edge frequency are highly localized.