基于狄拉克半金属和二氧化钒的三频带双调谐吸波体

Dual-tunable triple-band absorber based on bulk Dirac semimetal and vanadium dioxide

提出了基于狄拉克半金属(BDS)和二氧化钒(VO2)的三频带(triple-band)双调谐吸波体,通过时域有限差分法和等效电路模型(ECM)分析了吸波体的电磁特性。研究表明:当VO2呈现出纯金属态时,吸波体会出现三个明显的吸收峰,平均吸收率为98.64%。同时,通过改变BDS费米能量和VO2电导率可以动态调谐吸波体吸收峰处的谐振频率和吸收率。最后,分别讨论了吸波体吸波特性随BDS层、VO2层和中间介质层厚度的变化规律。这为多带双调谐滤波器、吸波体的设计提供了理论依据。

In this paper,a dual-tunable triple-band absorber based on bulk Dirac semimetal(BDS)and vanadium dioxide(VO2)is proposed.The electromagnetic properties of the absorber are analyzed by the finite difference time domain method and equivalent circuit model(ECM).When the VO2 is in fully metallic state,the absorption spectrum of the dual-tunable absorber exhibits three obvious absorption peaks with the average absorptance being 98.64%.The resonant frequencies and absorptivity of the absorber can be dynamically controlled by adjusting the Fermi energies of BDS and the conductivities of VO2.Finally,the relationships between the absorptivity of the dual-tunable absorber and the different thicknesses of the BDS,VO2 and immediate dielectric layers are further discussed.This work provides potential applications in the designs of multi-banddual-tunable filters and absorbers.