Physics and advanced simulations of photonic and plasmonic structures

In this contribution, we present the main results of our joint scientific theoretical project with the Czech Science Foundation (2010–2013) Physics and advanced simulations of photonic and plasmonic structures, arisen from the cooperation of three laboratories of Czech Technical University in Prague, Institute of Photonics and Electronics of the Academy of Sciences of the Czech Republic, and Brno University of Technology. First, we present the basics of our in-house methods and numerical tools for the analysis of such structures, developed independently within the scope of the project, together with their mutual comparison. Three linear frequency-domain modal three-dimensional (3D) numerical methods developed and adapted for modelling photonic / plasmonic guiding and resonant subwavelength (SW) structures, will be mentioned, namely, aperiodic rigorous coupled-wave analysis (aRCWA) method, bi-directional mode expansion propagation method (BEP) based on the Fourier series (BEX), as well as the finite difference (FD) / finite element (FE)-BEP technique, connecting the eigensolvers with advanced BEP-based scattering matrix algorithm. Subsequently, a special original method suitable for treating nonlinear structures with Kerr nonlinearities, based on the eigenmode expansion (EME), has been developed (NL-EME) and applied, too. These methods, together with several approximate methods, have formed a solid portfolio for subsequent analysis of various photonic and plasmonic subwavelength structures of interest. The project generated several novel and interesting results, introducing novel structure designs in the following areas: novel magnetooptic (MO) guiding structures with non-reciprocal properties, advanced plasmonic structures based on hybrid dielectric plasmonic slot waveguides, nonlinear plasmonic couplers, SW grating structured waveguides, 3D resonant high-Q nanostructures, gain-loss guiding structures as photonic analogues of quantum structures with parity-time (PT)-symmetry breaking. Selected results of modelling of these promising SW structure designs will be presented and discussed, together with a new result based on our recent investigation of the plasmon-soliton interaction.