The application of negative permittivity materials and metamaterials in electrically small antennas

This paper presents an overview of research at Bell Laboratories on the use of negative permittivity in electrically small antennas. This work began with a simple theoretical question: if we had a material with negative electric permittivity at microwave frequencies, could we use this material to construct a high performance electrically small antenna? The answer is yes: negative permittivity spheres can form the basis of effective small antenna elements with Q-factors at 1.5x the fundamental lower bound.