Introduction

1.1 Background

Electromagnetic waves form a vital part of our daily life since they are the basic building block for many of our regular amenities including digital imaging, sensing, and devices such as antennas, light sources, optical fibers, lenses, etc. Ranging from enormously low frequencies up to Gamma rays, the electromagnetic wave occurrences continuously received excessive attention while the interaction of matter and waves has been a focus of the extensive study of researchers.

Passage of electromagnetic waves through free space does not provide with interesting phenomena. It is the interaction of electromagnetic waves with the material that led to the numerous applications and devices mentioned earlier. Transmission of electromagnetic waves, their reflection, and diffraction are some of the many effects which result from the interaction of waves and material. Dielectric permittivity (ε) and the magnetic permeability (µ) are the two electromagnetic parameters that determine the materials response to an incident electromagnetic wave.

The response of ordinary materials is just a small part of the available literature. Aberrant material responses can be obtained by crafting intricate structures, also called Metamaterials. The phrase “Meta” is of Greek origin meaning “beyond.” These are those material designs which are composed of atoms that are on order of a fraction of the wavelength of light.

To provide a good description of the interaction of light and matter, one can take an average of the atomic scale. Therefore atomic detail is not very important. It is then considered as a homogeneous medium, and electromagnetic parameters can be defined. The flexibility provided by metamaterials of tailoring electromagnetic parameters of materials, within some theoretical limit, is an indispensable source of motivation and interest surrounding these structures.

Metamaterial research began in the early 21st century after successful demonstration of both negative permittivity and negative magnetic permeability (Smith, 2000). In spite of this, it started forty years ago, in 1968, due to the conceptual framework of negative ε and µ posted by a Russian physicist (Veselago, 1968). It took forty years and hard work by Sir John B. Pendry et al. (1999) for the actual realization of such a structure in Pendry, Holden, Robbins, and Stewart, 1999). Veselago et al. (1968) coined left-handed material as a term to refer to structures holding negative values of ε and µ simultaneously. One can achieve a negative refractive index that cannot be produced by naturally existing materials. The negative index reversed many known optical effects and changed the perspective of the scientists regarding the way they treat the optics and electromagnetics. From the year 2000 onwards, the area of metamaterials saw an increasing importance as the number of publications in metamaterials and other related fields doubled every ten months, efficiently following the famous Moore’s Law (Veselago, & Narimanov, 2006). It’s been sixteen years since the introduction of this field, and witnessed the publication of voluminous literature on this specific topic, indicating the interest of the scientific community in metamaterials and numerous journals covering the wide variety of issues of the metamaterial.