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We present SPARC: Simulation Package for Ab-initio Real-space Calculations. SPARC can perform Kohn-Sham density functional theory calculations for isolated systems such as molecules as well as extended systems such as crystals and surfaces, in both static and dynamic settings. It is straightforward to install/use and highly competitive with state- of-the-art planewave codes, demonstrating comparable performance on a small number of processors and increasing advantages as the number of processors grows. Notably, SPARC brings solution times down to a few seconds for systems with O(100 − 500) atoms on large- scale parallel computers, outperforming planewave counterparts by an order of magnitude and more. 

Metasurfaces present a potent platform to manipulate light by the spatial arrangement of sub‐wavelength patterns with well‐defined sizes and geometries, in thin films. Metasurfaces by definition are planar. However, it would be highly desirable to integrate metasurfaces with diverse, spatially programmed sub‐wavelength features into a 3D monolith, to manipulate light within a compact 3D space. Here, a 3D photoengraving strategy is presented; that is, generation of such composite metasurfaces from a single microstructure via the irradiation of multiple interference laser beams onto different facets of the parent azopolymeric microstructure. Through “photofluidization,” this technique enables independent inscription and erasing of metasurfaces onto and from individual facets of 3D monoliths with arbitrary shapes and dimensions, in a high‐throughput fashion (over approximately a few cm²at a time). By engraving discrete sub‐wavelength 1D surface relief gratings of different pitches on different facets of an inverse pyramidal array, a multiplexing structure‐color filter is demonstrated.