A dedicated finite-element solver enables accurate and fast simulations of light interaction with metallic nanostructures.With advances in nanotechnology growing at a fast pace, reliable simulations of nanooptical devices are crucial for research and development. Designing and optimizing the functionality of nanooptical components is typically assisted by computer simulations in combination with optical inspection as a critical step in product development and quality control. Dimensional metrology, for example, relies essentially on a numerical comparison of measurements with simulations. In addition, the latter are used in most scientific nanooptics publications to support theoretical and experimental results.The evolution of electric and magnetic fields in any welldefined nanostructure is described by Maxwell's equations. All information about the classical properties of light is contained in the electromagnetic fields, which is used to solve these differential equations. A variety of methods exist to perform rigorous simulations of Maxwell's equations. These include finite-element, finite-difference time-domain, Fouriermodal, and boundary-element approaches. However, especially (logarithmic scale, blue: low, red: high).for large 3D computational domains and highly conductive materials (like silver or gold), the electromagnetic fields of interest are so complicated that reaching accurate approximations becomes challenging for all numerical methods. It has even been suspected that nearly all published numerical results of light scattering off 3D metal nanostructures are of incorrect accuracy. 1 To approach this challenge, we use dedicated finite-element method (FEM)-based simulation tools, which enable significantly improved accuracy and relatively short computation times.
Dedicated FEM solver for nanooptics simulationsIn a joint effort between the Zuse Institute Berlin and JCMwave, we are developing the JCMsuite finite-element solver, a dedicated tool for nanooptical simulations. It has been applied successfully to a wide range of electromagnetic-field computations including metamaterials, 2 photonic-crystal fibers 3 (see Figure 1),
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