  Despite more than a decade of active research, the fundamental problem of
material loss remains a major obstacle in fulfilling the promise of the
recently emerged fields of metamaterials and plasmonics to bring in
revolutionary practical applications. In the present work, we demonstrate that
the problem of strong material absorption that is inherent to plasmonic systems
and metamaterials based on plasmonic components, can be addressed by utilizing
the time dimension. By matching the pulse profile to the actual response of a
lossy metamaterial, this approach allows to offset the effect of the material
absorption. The existence of the corresponding solution relies on the
fundamental property of causality, that relates the absorption in the medium to
the variations in the frequency-dependent time delay introduced by the
material, via the Kramers-Kronig relations. We demonstrate that the proposed
space-time approach can be applied to a broad range of metamaterial-based and
plasmonic systems, from hyperbolic media to metal optics and new plasmonic
materials.
