Title : Synergetic effects of plasmonic Ag nanoparticles and plasmonic WS2 nano disc hybrid underneath graphene layer for enhanced photodetector
Abstract:
Two-dimensional (2D) materials van der Waals (vdW) heterostructures, such as stacking Transition Metal Dichalcogenides (TMDs) on graphene, have improved the performance of optoelectronics devices. Also, plasmonic metal nanostructures enhance the light absorption in 2D materials and their heterostructures due to the strongly enhanced local field intensity around metal nanostructures. Here, we developed a photodetector based on Ag nanoparticles embedded in silica beneath the WS? nanodisc/graphene vdW heterostructure to improve the photodection through the coupling of plasmons and excitons. The device exhibits a high performance with a responsivity of 8 A/W, at a wavelength of 450 nm. This value of responsivity is at least 500% enhancement compared to the device without AgNPs. measured under the same conditions. This enhancement can be attributed to the strong coupling of the plasmons and excitons in the WS2 nanodiscs/graphene/AgNP heterostructures. In doped WS? nanodisc possibly generate the localized surface plasmon resonance (LSPR) and enhance the performance of the photodetector. This device is therefore a promising for high-performance optoelectronics application.
