Fig. 8
Summary and outlook for meta-optics. a Schematic showing the broad nonlinear conversion bandwidth for meta-optics. b Schematic showing the ultrafast response time for meta-optics based on metals and TCOs. c Schematic illustration of nonlinear wavefront control using meta-optics. d Schematic of generating coherent source in the ultra-short (UV and X-ray) or ultra-long (THz) wavelength band using meta-optics. e Illustration of possible directions for further enhancing the nonlinear conversion efficiency of meta-optics