ABSTRACT
One of the most fascinating elds of modern optics is that of optical metamaterials. ey are man-made structures with electromagnetic (EM) properties which are not met in naturally occurring materials such as arti cial magnetism and negative refractive index (Veselago, 1968; Pendry, 2000, 2004). e arti- cial magnetic response of the metamaterials can lead to strong paramagnetic (permeability μ > 1) and diamagnetic response (permeability μ < 1 or even μ < 0) of the same metamaterial structure, in frequency regions where such a response is not met in naturally occurring materials, like the near-infrared and optical regions where ordinary materials with strong magnetic response are very rare. Magnetic activity in these regions of the EM spectrum is of great technological importance since it allows for the realization of devices such as compact cavities, adaptive selective lenses, tunable mirrors, isolators, converters, optical polarizers, lters, and phase shi ers (Panina et al., 2002; Yen et al., 2004). Magnetic metamaterials realized at radio frequencies have already found application in magnetic resonance imaging (Wiltshire et al., 2001).
