  This paper studies time-dependent electromagnetic scattering from
metamaterials that are described by dispersive material laws. We consider the
numerical treatment of a scattering problem in which a dispersive material law,
for a causal and passive homogeneous material, determines the wave-material
interaction in the scatterer. The resulting problem is nonlocal in time inside
the scatterer and is posed on an unbounded domain. Well-posedness of the
scattering problem is shown using a formulation that is fully given on the
surface of the scatterer via a time-dependent boundary integral equation.
Discretizing this equation by convolution quadrature in time and boundary
elements in space yields a provably stable and convergent method that is fully
parallel in time and space. Under regularity assumptions on the exact solution
we derive error bounds with explicit convergence rates in time and space.
Numerical experiments illustrate the theoretical results and show the
effectiveness of the method.
