基于二氧化钒的可见光超材料饱和吸收体

Metamaterial absorbers are widely used in various fields due to their ability to achieve "perfect" absorption close to 100% at a specific wavelength. Metamaterials with saturable absorption properties can be used to control laser pulses, but the studies on the optical properties of metamaterials are mainly focused on infrared or terahertz bands, and there are few studies in visible bands. Based on the traditional three-layer structure model of the metamaterial absorber and the phase change characteristics of the vanadium dioxide which has the temperature-dependent electromagnetic parameters, a visible range metamaterial saturable absorber is designed. The absorptivity of this kind of absorber will be saturated with the increase of the temperature caused by the incident electromagnetic wave, and finally it will convert to a highly reflective state, which is similar to that of a semiconductor saturable absorber mirror. The numerical simulation of the structure shows that the average saturation depth is 16% in the wavelength range of 405-650 nm.