III-V nanowires on silicon (100) as plasmonic-photonic hybrid meta-absorber.

Integration of functional infrared photodetectors on silicon platforms has been gaining attention for diverse applications in the fields of imaging and sensing. Although III-V semiconductor is a promising candidate for infrared photodetectors on silicon, the difficulties in directly growing high-quality III-V on silicon and realizing functionalities have been a challenge. Here, we propose a design of III-V nanowires on silicon (100) substrates, which are self-assembled with gold plasmonic nanostructures, as a key building block for efficient and functional photodetectors on silicon. Partially gold-coated III-V nanowire arrays form a plasmonic-photonic hybrid metasurface, wherein the localized and propagating plasmonic resonances enable high absorption in III-V nanowires. Unlike conventional photodetectors, numerical calculations reveal that the proposed meta-absorber exhibits high sensitivity to the polarization, incident angle, wavelength of input light, as well as the surrounding environment. These features represent that the proposed meta-absorber design can be utilized not only for efficient infrared photodetectors on silicon but for various sensing applications with high sensitivity and functionality.