Multifunctional graphene-based optoelectronic structure based on a Fabry-Perot cavity enhanced by a metallic nanoantenna.

Optical communications systems are continuously miniaturized to integrate several previously separate optoelectronic devices, organized with silicon-based incorporated circuits, onto a distinct substrate. Modulators and photodetectors have essential roles in photonic systems and operate with different mechanisms. Integrating them into one device is complex and challenging, but these multifunctional devices have numerous advantages. This article uses a graphene/hBN-based structure to modulate, detect, and absorb any signal with the desired frequency in the THz range. The proposed system comprises one unpatterned graphene sheet embedded in bulk hBN with the periodic gold/palladium nanostructure beneath and below it. The perfect absorption, a modulation depth of 100%, and photodetection of more than 20 A/W at any desired frequency can be verified.