Huygens subgridding combined with the 2D fully collocated implicit FDTD method

The Huygens subgridding formalism is used to stably embed a fully collocated grid in the standard Yee scheme. This allows adaptive mesh refinement as well as the inclusion of complex materials such as good conductors, anisotropic media and plasmas. The overall stability limit on the time step is solely determined by the Courant limit of the main (Yee) grid. The paper focuses on the two-dimensional TE problem.