title: Enhanced spatial near-infrared modulation of graphene-loaded perfect absorbers using plasmonic nanoslits.
abstract: Modulating spatial near-infrared light for ultra-compact electro-optic devices is a critical issue in optical communication and imaging applications. To date, spatial near-infrared modulators based on graphene have been reported, but they showed limited modulation effects due to the relatively weak light-graphene interaction. In combination with graphene and metallic nanoslits, we design a kind of ultrathin near-infrared perfect absorber with enhanced spatial modulation effects and independence on a wide range of incident angles. The modulated spectral shift of central wavelength is up to 258.2 nm in the near-infrared range, which is more promising in applications than state-of-the-art devices. The modulation enhancement is attributed to the plasmonic nanoslit mode, in which the optical electric field is highly concentrated in the deep subwavelength scale and the light-graphene interaction is significantly strengthened. The physical insight is deeply revealed by a combination of equivalent circuit and electromagnetic field analysis. The design principles are not only crucial for spatial near-infrared modulators, but also provide a key guide for developing active near-infrared patch nanoantennas based on graphene.
authors.forename: Yijun
authors.initials: Y
authors.lastname: Cai
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Zhu
authors.forename: Qing Huo
authors.initials: QH
authors.lastname: Liu
authors.forename: Timothy
authors.initials: T
authors.lastname: Lin
authors.forename: Jianyang
authors.initials: J
authors.lastname: Zhou
authors.forename: Longfang
authors.initials: L
authors.lastname: Ye
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Cai