  We consider time-harmonic electromagnetic wave equations in composites of a
dispersive material surrounded by a classical material. In certain frequency
ranges this leads to sign-changing permittivity and/or permeability. Previously
meshing rules were reported, which guarantee the convergence of finite element
approximations to the related scalar source problems. Here we generalize these
results to the electromagnetic two dimensional vectorial equations and the
related holomorphic eigenvalue problems. Different than for the analysis on the
continuous level, we require an assumption on both contrasts of the
permittivity and the permeability. We confirm our theoretical results with
computational studies.
