Reducing complexity in photonic simulations: ZenScat — an efficient 2D RCWA solver

We present a comprehensive solver implementation of a 2D Rigorous Coupled Wave Analysis (RCWA), tailored specifically for conformal thin multilayer devices and 2D photonic crystals with arbitrary interface profiles. Unlike traditional diffraction efficiency analysis, our approach emphasizes beam-shaping applications. Thus, our solver uniquely incorporates parameter sweeps across both wavelength and angular domains. This enables effective optimization of devices, such as low-pass spatial filters. Our software streamlines the design and analysis of complex photonic structures, broadening the practical application of RCWA methods and enabling the rapid development and optimization of novel photonic components.