We numerically propose a dual-band absorber in the infrared region based on periodic elliptical graphene-black phosphorus (BP) pairs. The proposed absorber exhibits near-unity anisotropic absorption ...for both resonances due to the combination of graphene and BP. Each of the resonances is independently tunable via adjusting the geometric parameters. Besides, doping levels of graphene and BP can also tune resonant properties effectively. By analyzing the electric field distributions, surface plasmon resonances are observed in the graphene-BP ellipses, contributing to the strong and anisotropic plasmonic response. Moreover, the robustness for incident angles and polarization sensitivity are also illustrated.
We theoretically investigate the anisotropic plasmonic resonances in the proposed infrared absorber, which consists of stacked graphene-black phosphorus (BP) bilayers with dual absorption peaks. By ...combining the advantages of graphene and BP, stacked graphene-black phosphorus bilayers exhibit high absorption rates at both peaks and strong anisotropy. The loss mechanism is revealed deeply with electric field distributions, while the near field coupling between graphene and BP is discussed detailedly. Furthermore, by altering the corresponding doping levels of graphene and BP, each of the absorption bands can be independently tuned effectively. The angular dependence for oblique incidence is illustrated by performing a series of simulations. Besides, polarization-sensitivity for stacked graphene-BP bilayers (GBPBs) is also presented. Thus, our approach provides a theoretical and systematic guide for designing a variety of multi-resonant graphene-BP-based spatial absorbers, which show potentials in the applications of sensors and reflective polarizers.
Near-infrared plasmonic metamaterial absorbers based on graphene are designed with active optical absorption and independence on a wide range of incident angles. They have strong electrical ...modulation effects due to the plasmonic slit mode. The physics inside is deeply revealed by the electromagnetic field analysis.
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