Introduction and Overview of the Book

his chapter discusses the history of metamaterials (MTMs) dates back to the nineteenth century with numerous contributors, many of whom have only recently been rediscovered. In many vacuum electron devices, the particle wave interaction is mediated in part via a material, where the functionality of the material manipulates the electromagnetic wave in a controlled fashion. The scale of the inhomogeneities distinguishes metamaterials from many other electromagnetic media. These last two sentences from Wei are critical in defining the underlaying physics that enables us to consider MTMs as “effective media.” The chapter examines how to determine the material's effective permittivity and permeability from measurements of the scattering parameters. Double NeGative media materials consist of resonant elements where the operation of the material at resonance is necessary to achieve a DNG response. The chapter also presents an overview on the key concepts discussed in this book.