提出了一种以金属-电介质复合结构为基本单元的磁导率μ近零的太赫兹超材料。在太赫兹波垂直入射的情况下,当电场为横磁偏振时,在1.44 THz谐振频率附近,可得到μ实部的最优值为0,μ近零的带宽(|μ|<0.05)约为0.2 THz;当电场为横电偏振时,在0.978 THz谐振频率附近,得到μ实部的最优值为0,μ近零的带宽(|μ|<0.05)约为0.1 THz。在固定的几何参数下,通过改变偏振方向可以实现该超材料在不同频段内的近零效果。分析了聚酰亚胺介质层厚度、金属层数以及入射角度对磁导率近零效果的影响,并讨论了该结构的容差范围。

A kind of terahertz metamaterial with a near-zero magnetic permeability (μ) which uses a metal-dielectric composite structure as the basic unit cell is proposed. Under the condition that the terahertz wave is incident perpendicularly, the optimal value of the real part of μ is 0 near the resonance frequency of 1.44 THz with a bandwidth (|μ|<0.05) of about 0.2 THz when the electric field is transverse-magnetic polarized. However, when the electric field is transverse-electric polarized, the optimal value of the real part of μ is 0 near the resonance frequency of 0.978 THz with a bandwidth (|μ|<0.05) of about 0.1 THz. Under the fixed geometric parameters, the μ-near-zero effect can be achieved in different frequency bands via the adjustment of polarization direction. The influences of the thickness of polyimide dielectric layer, metal layer number, and incident angle on the μ-near-zero effect are analyzed, and the tolerance error range of this structure is discussed.