基于α-MoO₃光栅型吸收控制超表面

Grating-Type Controllable Absorption Metasurfaces Based on α-MoO₃

设计了基于α相三氧化钼(α-MoO3)的三层结构吸收器。该结构顶层为α-MoO3光栅,中间为电介质,底部为金层。模拟结果表明,当TE波正入射时,超表面在19.36 μm处存在吸收峰,吸收率达到99.6%。与单层α-MoO3对TE波的吸收相比,超表面的吸收率大幅增加。此外研究了晶轴方向和入射角度对吸收率的影响,结果表明可以通过改变晶轴方向来调节吸收峰位置,并且超表面对入射角度不敏感。设计的超表面在光学滤波器和传感方面具有潜在的应用价值。

A three-layer structure absorber based on α phase molybdenum trioxide (α-MoO3) was designed. The structure was composed of a top layer of α-MoO3 grating, a dielectric layer in the middle and a gold layer at the bottom. The simulation results show that the absorption peak existed at 19.36 μm when TE wave was normal incidence, and the absorption reached 99.6%. Compared with the absorption of TE wave by monolayer α-MoO3, the absorption of metasurface increased greatly. Furthermore, the effects of crystal axis direction and incidence angle on absorption were also studied. The results show that the position of absorption peak can be adjusted by changing the direction of crystal axis, and the metasurface was insensitive to the incidence angle. The design of the metasurface provides potential applications for optical filters and sensors.