Review of models for complex materials and fine features in time-domain simulations

Summary form only given. Time-domain simulations such as those based on the FDTD and TLM methods are a powerful means of numerical experimentation, offering users an unparalleled access to the evolution of complex electromagnetic phenomena. As applications span a wider frequency range and materials are employed over a wider parameter domain it is necessary to characterise more fully the behaviour of materials over wide frequency ranges in the presence of non-linearities, anisotropies, and magneto-electric coupling. Similarly, as confidence increases in the use of simulation tools it becomes more important to maintain accuracy and at the same time limit computational demands to allow for interactive use of models for design optimisation. This requires special techniques to deal with fine features which add only marginally to computational demands. Previous advances in the modelling of complex materials are described, which allow efficient algorithms to be embedded into time-domain codes to describe very general material properties. Similarly, the way in which fine features may be modelled are described with reference to either customised nodes or hybrid techniques. Numerical examples are shown and an attempt is made to outline outstanding problems and future developments