偶极源辐射超材料表面波的存在条件及特性

Analysis of surface waves in metamaterials based on dipole radiation sources

为了更好地利用超材料,需要研究半空间模型中超材料的表面波.利用电磁波反射场的索末菲积分,应用复变函数积分的鞍点法,研究下层介质分别为等离子体、负磁性介质和左手材料时,在竖直电偶极子与磁偶极子的反射场中所含表面波的成分构成与电磁特性.确定了各表面波模式发在的条件,给出了侧面波或吸附表面波模式与入射电磁波的类型、下层介质的等效介电常数等的关系.

For the better use of metamaterials,the surface waves of metamaterials are studied in half-space model with dipole radiation source.Using the Sommerfeld integrals of TM wave and TE wave,the branch-cut’s effect on the computation of the integrals is investigated based on saddle point algorithm.The distribution and validity of pole points for the integrands is analyzed according to the properties of complex integral.For TM wave,there are lateral wave and Zenneck surface wave in the case of taking left-handed material as substrate;for TE wave,no Zenneck surface wave can exist in any case of metamaterials.