Abstract
As a natural biaxial hyperbolic material,α-phase molybdenum trioxide(α-MoO3)exhibits dielectric and metallic properties in the plane,rendering it an exceptional candidate for polarization-dependent devices.In this work,we design a lithography-free polarization-dependent absorber consisting of an α-MoO3 film,a germanium layer,and a silver substrate.The results show that a narrowband absorption of up to 0.99 is achieved at a wavelength of 12.2 pm for transverse magnetic polarization.In contrast,the absorption is only 0.06 at this wavelength for transverse electric polarization.This remarkable polarization-dependent absorption performance is attributed to the coupling of epsilon-near-zero modes and Fabry-Perot resonances,which is confirmed by the electric field and power dissipation density distributions.Furthermore,strong polarization-dependent performance could also be achieved when the crystal axis of α-MoO3 is rotated in the out-of-plane.This work demonstrates that in-plane anisotropic α-MoO3 has the potential for designing high polarization-dependent devices.
基金项目
National Natural Science Foundation of China(52106099)
Shandong Provincial Natural Science Foundation(ZR2022YQ57)
Taishan Scholars Program,and Basic and Applied Basic Research Fund Project of Guangdong Province(2019A1515111178)
万方数据