Dispersion Properties of Multilayered Metal-Dieletric Metamaterials
  We study dispersion properties of layered metal-dielectric media having different layers thicknesses ratios. Plotting dispersion diagrams and isofrequency contours, we find that strong nonlocality is inherent property of such periodic structures. We introduce different level of losses and analyze complex modes of the metamaterial demonstrating that it operates in a regime with infinite numbers of eigenmodes, with nonlocality slightly affected by losses. 
Alexey A. Orlov, Ivan V. Iorsh, Pavel A. Belov, Yuri S. Kivshar
physics.optics