【摘要】 设计了一种基于不同半径的二氧化钒（VO₂）圆环加载于介质层上的宽带可调超材料吸波器,利用VO₂随温度变化的相变特性,实现了外部温度对吸收曲线的动态调节.通过仿真计算表明,该吸波器在外部温度为350K时在8.09～11.23THz带宽范围内吸收率可达90%以上,表现出高吸收特性;而外部温度为300K时在相同频段内吸收率始终低于20%,从而实现了对电磁波吸收的可调功能.进一步对吸波器的等效阻抗和电场分布进行分析讨论,阐明VO₂对吸收性能的调节机制.此外,文章讨论了结构参数、偏振角以及入射角对吸收的影响.其结果表明,合理选择结构参数可实现吸收性能与偏振角、入射角的无关性.本文的结论对于设计其它类型的超宽带可调吸波器具有重要的指导意义.更多还原

【Abstract】 A broadband tunable metamaterial absorber based on vanadium dioxide（VO₂） rings with different radius loaded on the dielectric layer is designed.The phase transition characteristics of VO₂ with temperature are used to realize the dynamic adjustment of the absorption curve of external temperature.Simulation calculations show that the absorber can reach more than 90% in the bandwidth of 8.09～11.23 THz when the external temperature is 350 K,showing high absorption characteristics; while the absorption coefficient in the same frequency band is always lower than 20% when the external temperature is 300 K,achieving the adjustable function of electromagnetic wave absorption.The equivalent impedance and electric field distribution of the absorber are further analyzed and discussed,and the adjustment mechanism of VO₂ on the absorption is clarified.In addition,the article discusses the effects of structural parameters,polarization angles,and angles of incidence on the absorptivity.The results show that reasonable selection of parameters of the structure can achieve the independence of the absorbing performance from the polarization angle and the angle of incidence.The conclusions of this paper have promising potential for designing other types of ultra-wideband tunable absorbers.更多还原