双层金属环形阵列的太赫兹表面等离子体研究

摘要

When a metal-dielectric-metal structure is illuminated by vertical incidence of terahertz wave,the character-istic of transmission spectra and the relationship with surface plasmon resonance are studied.The electric field distri-butions of the resonance modes in transmission spectra confirms the confinement of surface plasmon and the propaga-tion mechanism of surface electromagnetic waves and process of energy flow.Based on dispersion curve of the struc-ture,propagating surface plasmon and localized surface plasmon principally dominated the lower and higher reso-nances,respectively.By changing the parameters of the structure,further studies show that besides the two SP modes mentioned above,coupling of SP modes as well as quasi-rectangular waveguide effect generated in the air loop signifi-cantly modifies the terahertz transmission.%研究了太赫兹波垂直通过具有周期性亚波长环形空气槽阵列的金属-介质-金属三层结构的透射谱特性，以及与表面等离子体谐振的关系。共振模式电场分布与色散曲线分别表明：表面等离子体具有束缚性，表面电磁波的传输机制与能量流动过程，透射谱的两个共振峰与传播性的表面等离子体模式、局域化的表面等离子体模式及其耦合有关。改变结构的几何参数，其共振峰变化趋势进一步印证了以上观点，并且空气环中激发的准波导效应也影响了太赫兹波的传输。