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提出了一种由二氧化钒(VO2)和金属Au构成的吸收带宽可调谐的超材料完美吸收器(MPA).模拟发现,该MPA的吸收波长覆盖了可见光和近红外光.改变VO2温度,MPA的吸收带宽可实现0.378 μm的调谐.分析MPA在吸收波长处的磁场分布发现MPA激发了表面等离子激元共振,实现在可见光和近红外光完美吸收.本文提出的MPA可应用于智能设备和热发射器等当中.“,”Metamaterial Perfect Absorber(MPA)is currently a research hotspot because of its numerous advantages such as high absorption efficiency,ultra-thin thickness,simple structure and so on.Since Landy et al.first proposed an MPA with perfect absorption characteristics,different types of MPAs have been proposed,and the absorption wavelengths over microwave,terahertz,infrared,and visible bands have been identified.However,once the structural parameters of MPA are fixed,the absorption bandwidth of MPA almost cannot be dynamically adjusted,which will limit its applications in some particular fields.This paper proposes a bandwidth-tunable MPA which is composed of vanadium dioxide(VO2)and Au.The research group simulated and analyzed the MPA based on Finite Difference Time Domain(FDTD)method.In the simulation,a periodic boundary condition was added in x-and y-directions,and a perfect match layer was added in the z-direction as the boundary condition.The polarization of the incident light was set to be TM polarization(Along the x axis).Incident light was perpendicular to the surface of the structure,which indicated the incident angle θ is 0.The simulation results show that the tuning range of absorption bandwidth can achieve 0.378 μm by controlling the temperature of VO2,and the absorption wavelength of MPA covered visible and near-infrared light.To explore the physical explanation for the high absorption efficiency in different wavelengths,we analyzed electromagnetic field distribution in MPA in different wavelengths,and revealed that although the high absorption efficiency is caused by the incident-light-stimulated surface plasmons in MPA,the working mechanism in visible and near infrared wavelength is quite different.In visible light range,no matter vanadium dioxide is in metallic state or dielectric state,the high absorption efficiency is caused by Propagating Surface Plasmon(PSP).On the other hand,for near-infrared light,if vanadium dioxide is in dielectric state,the high absorption efficiency is due to the Localized Surface Plasmon(LSP);or if vanadium dioxide is in metallic state,the high absorption efficiency is due to Fabry-Perot(FP)cavity resonance.Our results show that the MPA has the potential to be used in applications such as optical integrated devices and thermal emitters.