Left-handed materials in metallic magnetic granular composites

摘要

There is recently interests in the ``left-handed '' materials. In thesematerials the direction of the wave vector of electromagnetic radiation isopposite to the direction of the energy flow. We present simple arguments thatsuggests that magnetic composites can also be left-handed materials. However,the physics involved seems to be different from the original argument. In ourargument, the imaginary part of the dielectric constant is much larger than thereal part, opposite to the original argument.