Low‐Dimensional Plasmonic Photodetectors: Recent Progress and Future Opportunities

Abstract Plasmonic nanostructures can achieve subdiffraction‐limit light confinement with enhanced electric fields. By taking advantage of the light‐confinement effect, various plasmonic photodetectors that combine low‐dimensional (LD) semiconductor structures and plasmonic materials have recently demonstrated excellent plasmon‐enhanced device performance and attracted significant research interest. In this review, the state‐of‐the‐art progress in the development of various LD photodetectors with different plasmonic structures is briefly surveyed, in order to provide a clear picture of related fabrication methods, leading to maximized plasmonic enhancement. The fundamentals of localized surface‐plasmon resonance and plasmonic hot electrons are first introduced, followed by a summary of several prototypical LD photodetectors enhanced by metal nanoparticles (NPs), including noble‐metal NPs, poor‐metal NPs, and some plasmonic doped‐semiconductor NPs. The recent achievement of the newly developed LD photodetectors propelled by plasmonic hot carriers is also highlighted. Finally, some challenges and issues that need to be resolved in this field are proposed.