含左手材料和单负材料三层平板波导中TE模的传输特性

Propagation properties of TE mode in three layer slab waveguides with left-hand materials and single-negative materials

研究了以左手材料为衬底和单负材料为覆盖层三层平板波导中TE模的传输特性,为波导器件的设计提供了理论支持。导出了归一化有效厚度H与归一化频率v的关系,数值计算分析了三层平板波导的传输特性。结果表明,该三层平板波导TE模具有以下特性:1)当导波层与衬底或覆盖层磁导率的比值增大时,归一化有效折射率b随频率v的变化率减小。2)当不对称因子a趋近于0时,b随v单调变化;当a较大时,在截止频率附近,TE_1、TE_2、TE_3、TE_4和TE_5模出现双值现象。3)当a增大时,H-v曲线从左向右移动。4)对于TE_0模,H出现负值。

The propagation properties of TE mode in three layer slab waveguides with left-hand materials as substrate and single-negative materials as cover layer were investigated,providing theoretical support for the design of waveguide device.The dependence of normalized effective waveguide thickness H on normalized frequency v for the modes of three layer slabs was worked out.The propagation properties of TE mode in three slab waveguides were analyzed.The results show that the change rate of the normalized effective refractive index b with normalized effective frequency v is decreased with increasing the ratio of permeability of guided wave layer to substrate or superstratum.As the asymmetric value a approaches to zero,b varies with v monotonically.While the asymmetric value is big enough,there is two-value phenomenon for TE1, TE2,TE3,TE4 and TE5 modes near cutoff frequency.When the asymmetric value increases,the curve H-v shifts from left to right.H will be negative for TE0 mode.