用于构成左手化材料(LHMs)的开口谐振环的研究

考虑到谐振环几何形状和相互作用等因素,利用细铜丝制作了六边形开口谐振环(split ringresonator),研究了单个和多个谐振环在微波X波段(8-12GHz)的电磁响应行为。研究结果表明:对于单个谐振环,开口位置影响谐振频率和透射率;谐振环径向间距的在一定范围内增大,谐振频率将向高频移动,当径向间距进一步增大时,谐振频率反向低频移动;同时,谐振环的透射率将持续下降;当开口间距增大时,谐振频率将向高频移动;对于谐振环列(SRRs),谐振环间的相互作用促使谐振环列的透射率峰值明显下降,随着环间距的增大,谐振环列的谐振频率下降,透射率降低;对于一定的环间距,开口存在着一个最佳值,此时,谐振环列发生一次谐振,透射率较低,相反,谐振环列发生两次谐振。

The Investigation of Split-ring Resonators used to Constitute Left-handed Materials

Considered the dimension and interaction between split ring resonators (SRRs), hexagonal SRRs were prepared using thin copper wires and its response to X-band (8 - 12GHz) microwave was investigated experimently. For an individual SRR, It is showed that the resonance frequency and resonance transmission are influenced by the position of azimuthal gap. The resonance frequency will move to higher values as the radial gap expands at first, but it will fall to lower when the radial gap becomes much larger. And the resonance transmission will always descend at the same time. When the azimuthal gap increases, the resonance frequency will move to higher values. For the SRRs, the resonance transmission is weakened by the interaction of SRRs. The resonance frequency shifts towards lower values and the resonance transmission gets larger with the increases of separation distance. And when the separation distance is fixed, there is an optimal space of the azimuthal gap, which leads to lower transmission, otherwise, two resonances appear.