In the past several years, metasurfaces have emerged as one of the rapidly growing research fields in optics. These ultrathin arrays composed of subwavelength meta-atoms enable precise control of the various aspects of electromagnetic waves and have been proposed for a wide variety of applications such as lenses, polarization control, holography, coloration, spectroscopy, and many more. Due to recent advancements in nanofabrication processes as well as dramatic improvements in the performances of metasurfaces (efficiency, bandwidth, etc.), this technology has matured sufficiently to be incorporated into commercial applications. In this perspective, the various applications of metasurfaces are briefly reviewed, with focus put on the maturity level of the technology and applications for commercialization. First, the principal properties of metasurfaces are introduced, and the various potential applications are reviewed. Then, the maturity level of metasurface technology for these applications is discussed in terms of the potential added value, cost, and timeline. Finally, an outlook of the short-, intermediate-, and long-term opportunities for real-life applications is presented as well as the long-range challenges for future applications.
- flat optics