Plasmonic metasurfaces: Light-matter interactions, fabrication, applications and future outlooks

Plasmonic metasurfaces (PMs) consist of thin, sub-wavelength layers formed by meta-atoms derived from metallic nanostructures, designed to manipulate the interaction between electromagnetic fields and matter. The collective features of PMs are determined by both the properties of the nanoparticles (NPs) and the symmetry, dimensions, order, and orientation of the underlying superstructure. These combined characteristics enable PMs to play a crucial role in applications such as sensing, energy harvesting, nanolasing, nonlinear optics and surface-enhanced spectroscopy. This review focuses on three main aspects of PMs: light-matter interactions, fabrication methods, and applications. The near-field and far-field optical properties of various plasmonic superstructures, from the simplest individual nanostructures to more complex one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) PM superstructures, are systematically analyzed. Following this, a summary of the techniques employed for the fabrication of these PMs is provided, covering top-down, bottom-up, and hybrid strategies. The diverse applications of PMs, including their weak and strong coupling with 2D materials, luminescent molecules, chiral molecules, quantum dots (QDs), upconversion materials, and more, are also discussed. The review concludes by highlighting the current challenges and future perspectives in PMs, along with insights into their potential advancements towards the next generation of nanophotonic platforms.