引入归一化频率、归一化传播常数和非对称量等参数,研究了衬底是左手材料的介质平板波导中的表面模,得到用归一化参数表示的色散关系。用解析法计算了色散曲线,结果表明,材料参数对左手材料平板波导色散特性的影响很大。有的情况下只有TE1表面模存在,而有的情况下TE0表面模和TE1表面模都存在。有时TE1表面模与零阶振荡模圆滑连接,形成一个完整的曲线,有时会出现双重简并现象。分别讨论了TE表面模和TM表面模。
Paramaters such as normalized frequency, normalized propagation constant and asymmetry measure are introduced to study the surface modes of a dielectric slab waveguide with a left-handed material (LHM) substrate. The dispersion relations expressed by normalized parameters are then derived. Universal dispersion curves have been obtained analytically. It is found that dispersion properties differ dramatically for different LHM constitutive parameters. Some times surface TE0 mode does not exist, and some times both surface TE0 mode and surface TE1 mode exist. Some times the dispersion curve of TE1 surface mode continues with that of oscillating mode. It seems that the two different kinds of TE modes compensate each other to form one whole mode. And some times double degeneracy happens. Both TE and TM surface modes are discussed.