https://dukespace.lib.duke.edu/items/96e62305-2534-4aee-b8db-04a06e91019f
Negative refraction in three-dimensional point-dipolelike polaritonic crystals
We propose two practical realizations of the point-dipole crystal, shown previously to be capable of negative refraction and other metamaterial and plasmonic...
three dimensionalnegativerefractionpointcrystals