基于微扰方法分析非对称金属包覆左手介质平板波导的特性,给出了该波导的复有效折射率的一级近似解,并对波导的传输特性和损耗特性进行了数值模拟.结果表明:非对称金属包覆左手介质平板波导没有零阶模式;TE1模传播系数随波导厚度的增加迅速减小,损耗系数随波导厚度的增加快速增加,达到最大值后又迅速减小;非对称金属包覆左手介质平板波导传输特性相对于左手介质三层平板波导传榆特性发生了很大改变,TM1模,TM2和TE2模式以及更高阶模式在截止厚度附近出现双值现象;特别在二阶及高阶模式中,TE模式相对于TM模式具有高传输低损耗的特性,而以右手介质为芯层的金属包覆波导不具有这一特性.
Based on the perturbation method, the properties of asymmetric metal-clad slab waveguide with left-handed materials were discussed. The first order approximate solution of complex effective refractive index was obtained, and its transmission and attenuation characteristic curves were also numerically simulated. The simulation results show that there is no zero order mode in asymmetric metal-clad slab waveguide with Left-handed materials,the transmission coefficient of TEl mode quickly decreases with the increase of waveguide thickness, and its attenuation coefficient decreases sharply after increasing to a maximum. Besides, for TM1, TM2, TE2 modes, and other higher order modes, there are the diadic phenomenon nearby cut-off thickness, and especially in the case of the second order and other higher order modes. The transmission coefficient of TE mode is higher than that of TM mode, but the attenuation efficiency of TE mode is less than that of TM mode. However,those character do not appear in asymmetric metal-clad slab waveguide with right-handed materials.