Plasmonic nanodevices: Materials, micro-nano structures and performance

Plasmonic nanodevices take advantage of unique optical and electronic properties of surface plasmons that enable breakthrough in photonics, energy conversion and sensing, thus have evolved considerably over the past decades. Unlike traditional optical devices limited by the diffraction of light, plasmonic nanodevices modulate light at nanoscale, bridging the gap between photonics and electronics. The design and fabrication of effective plasmonic nanostructures is fundamental and vital to achieve high-performance nanodevices, recent advancements include the material innovations, microstructure design, fabrication techniques and photothermal applications at even unimolecular resolution. Therefore, numerous plasmonic sensing strategies have been developed and intensively employed to optoelectronic single-molecule sensing based on distinct principles. This review first outlines the material foundations and micro-nano fabrication methodologies for plasmonic nanodevices, and then summarizes the common designs of nanostructures in the field of optical sensing. Furthermore, some latest reports are introduced, focusing on their classification, design principles and optimization. The applications of plasmonic nanostructures with emphasis on several single-molecule sensing strategies are subsequently discussed. The study of single-molecule chemical reaction mechanisms and the control of matter transport via plasmonic solid-state nanopore transport are also introduced, followed by a perspective.