FORM-INVARIANCE OF MAXWELL'S EQUATIONS IN COORDINATE TRANSFORMATIONS: METAMATERIALS AND NUMERICAL MODELS


Ozgun O., KUZUOĞLU M.

METAMATERIALS: CLASSES, PROPERTIES AND APPLICATIONS, ss.87-136, 2010 (Hakemli Dergi) identifier

Özet

Metamaterials - artificial materials with engineered electromagnetic properties-is a young but rapidly growing topic that breaks down traditional rules, and fascinates scientists in the field of physics, optics and electromagnetics One of the major breakthroughs in the development of metamaterials is the cloaking device for obtaining electromagnetic invisibility, which can bend light around an object as if it weren't there The design of the cloaking device is realized by the coordinate transformation technique, which is based on the fact that Maxwell's equations are form-invariant under coordinate transformations In other words, Maxwell's equations preserve their form inside the transformed space, but the medium transforms into an anisotropic medium so that the electromagnetic fields are tuned by the coordinate transformation Although the coordinate transformation technique has long been used in electromagnetics/physics, the novel interpretation of this technique in realizing a cloaking device has emerged as one of the most exciting subjects in science and the general public alike In this chapter, we present a variety of transformation media, based on two interpretations of the coordinate transformation technique (i) The first interpretation is the design of anisotropic metamaterials to achieve certain goals, such as electromagnetic reshaping (called metamorphosis) within the framework of electromagnetic scattering and waveguides Apart from such fascinating -sometimes even science-fiction like-techniques, we demonstrate perfectly matched double negative (DNG) layers realized by complex coordinate transformations, (ii) The second interpretation is the modification of the computational domain of the finite methods for the purpose of efficient numerical simulations via uniform and easy-to-generate meshes in computational electromagnetics/physics All techniques will be supported by both analytical formulations and representative numerical simulations