Artificial dielect
Artificial dielectrics are artificial electromagnetic materials consisting of arrayed, synthetic substances. The arrays themselves, and the distances between synthetic substances are usually evenly spaced on, or within, a substrate. Hence, the arrays of inclusions are in a periodic or lattice structure. The lattice spacing is smaller than the impinging electromagnetic wavelength of interest. These were first conceptualized, constructed and deployed for interaction in the microwave frequency range in the 1940s and 1950s. The constructed medium, the artificial dielectric, has an effective permittivity and effective permeability, as intended.
In addition, some artificial dielectrics may consist of irregular lattices, random mixtures, or a non-uniform concentration of particles.
Artificial dielectrics came into use with the radar microwave technologies developed between the 1940s and 1970s. The term "artificial dielectrics" came into use because these are macroscopic analogues of naturally occurring dielectrics. The difference between the natural and artificial substance is that the atoms or molecules are artificially (human) constructed materials. Artificial dielectrics were proposed because of the need for lightweight structures and components for various microwave delivery devices
