MAXIM: Metasurfaces-oriented electromagnetic wave simulation software with intuitive graphical user interfaces

We develop MAXIM which is electromagnetic wave simulation software based on rigorous coupled-wave analysis. The principal advantage of MAXIM is an intuitive graphical user interface drastically improving the accessibility of the software to who are not familiar with computer programming. Here, we present the basic formulation and computation methods that are incorporated in MAXIM. The computation performance is also evaluated for several didactic examples of dielectric metasurfaces which are the main application of MAXIM. The comparison of the calculation results with commercial software based on a finite-difference time-domain method confirms that the computation results of two programs coincide closely with each other within 1% difference. Considering the easy accessibility, wide availability and high reliability, MAXIM will serve the development of related research fields of metasurfaces and nanophotonics. Program summary: Program Title: MAXIM CPC Library link to program files: https://doi.org/10.17632/352jpd593h.1 Licensing provisions: LGPL Programming language: Python 3.8 Supplementary material: User guide and tutorial movie Nature of problem: Time-harmonic electromagnetic wave simulations on multilayered periodic structures composed of isotropic materials. Diffraction occurs as a propagating electromagnetic wave meets periodically-structured arrays of materials that have different refractive indices. Wave parameters such as amplitude and phase of diffracted waves are modulated depending on the structure configuration. The main purpose of this software is to calculate complex transmission and reflection coefficients of diffracted waves from dielectric metasurfaces that are composed of arrays of subwavelength antennas. Solution method: Rigorous coupled-wave analysis associated with an extended scattering matrix method. According to Bloch's theorem, diffracted waves from periodic structures can be represented as a truncated Fourier series in which the primitive reciprocal vector is the same as that of periodic structures. Appropriate boundary conditions at the interface of a single structure layer enable development of an eigenvalue equation for which the solution gives a scattering matrix of the layer, and the coupling coefficients within it. In the case of a multilayered structure, a total scattering matrix can be obtained using the Redheffer star product, which interconnects scattering matrices of each layer. Total coupling coefficients can be also calculated using the extended Redheffer star product; this ability is a major advantage of the extended scattering matrix method. Diffraction from periodic structures can be fully described by the total scattering matrix and total coupling coefficients. Additional comments including restrictions and unusual features: MAXIM builds on several open-source Python packages including PySide2 [1], Numpy [2], Scipy [3], Pandas [4], Matplotlib [5] and Pyinstaller [6]. References [1] PySide2, https://wiki.qt.io/Qt_for_Python [2] Numpy, https://numpy.org/ [3] Scipy, https://www.scipy.org/ [4] Pandas, https://pandas.pydata.org/ [5] Matplotlib, https://matplotlib.org/ [6] Pyinstaller, https://www.pyinstaller.org/index.html