转移矩阵法在负折射率介质材料平板波导中的应用研究

Transfer Matrix in a Negative-refractive-index Medium and Its Application to the Investigation of Characteristics of a Left-handed Waveguide

利用严格电磁理论,推导出了适用于负折射率介质材料光波导的转移矩阵,分析讨论了转移矩阵的性质和应用.利用转移矩阵方法,推导出导波层为负折射率介质材料、覆盖层和衬底为右手材料的三层对称介质光波导的本征色散方程.用图解法研究了负折射率介质波导中TE波的异常色散特性.在负折射材料介质波导中没有零阶模,最低阶为1阶模,并且有截止频率,只有波导参量满足一定条件的时候才会存在,导模的横向波数可以为实数和纯虚数,而正折射率介质波导导模的横向波数只能为实数.

The transfer matrix of the slab waveguide made up of a negative-refractive-index material is solved using the rigorous electromagnetic wave theory. The characters and application of the transfer matrix were also discussed. The dispersion relations of the three-layer symmetric slab waveguide possessing a negative-refractive-index guiding layer and positive-refractive-index surrounding medium are investigated by the transfer matrix method. The exotic properties of guided transverse electric（TE） waves in a left-handed waveguide were investigated graphically. There are no fundamental modes in a left-handed waveguide. The lowest mode was the first-order mode which had cutoff frequency. The first-order mode exits only when the parameters of the left-handed waveguide satisfied certain terms. Guided modes existed both for imaginary transverse wave numbers and real transverse wave numbers in a left-handed waveguide, while guided modes only exist only for real transverse wave numbers in a right-handed waveguide.