Near-infrared photodetector based on few-layer MoS2 with sensitivity enhanced by localized surface plasmon resonance

Two-dimensional layered molybdenum disulfide (MoS₂) exhibits great potential for applications in optoelectronic devices, especially photodetectors. However, most of the reported MoS₂-based photodetectors only show limited absorption in visible range, resulting in narrow spectral response with poor sensitivity. Integrating plasmonic nanoparticles with MoS₂ provides a promising approach to enhance light-matter interactions and detector responsibility. We here report a plasmon-enhanced photodetector based on Au/MoS₂ heterostructure with Au nanoparticles (NPs) deposited on the surface of few-layer MoS₂ by magnetron sputtering. By coupling with Au NPs, the interactions between ultra-thin MoS₂ and incident lights are greatly enhanced via localized surface plasmon resonance. With this new architecture, the spectral response of few-layer MoS₂ based photodetector is extended to near-infrared region (700–1600 nm). Further, measurements show that significant improvement of photocurrent is observed with the highest value reaching up to 64 mAW⁻¹ at incident wavelength of 980 nm. With the demonstrated superb performance the proposed detector represents a viable path towards implementing ultra-sensitive near-infrared detection.