Fig. 1: Strategies for metasurface design.
From: High-efficiency, large-area, topology-optimized metasurfaces
a Conventional approaches sample the desired phase profile at discrete points and specify phase shifting elements to form a nanoscale phased array. b Our approach is to divide the desired phase profile into wavelength-scale, linear sections and use topology optimization to design each section individually. c Computation time versus device size for topology-optimized metasurfaces that are designed using two approaches: direct optimization of the entire metasurface (orange) and optimization of the metasurface after division into 3λ-wide sections (green)
