66. METAMATERIALS-

♤ “Metamaterial” refers to any material that gains its properties from structure rather than composition. Metamaterials have been used to create microwave invisibility cloaks, 2D invisibility cloaks, and materials with other unusual optical properties. Mother-of-pearl gets its rainbow color from metamaterials of biological origin. Some metamaterials have a negative refractive index, an optical property that may be used to create “Superlenses” which resolve features smaller than the wavelength of light used to image them! This technology is called subwavelength imaging.

♤ Thus, Metamaterials are artificial materials engineered to have properties that may not be found in nature. Metamaterials usually gain their properties from structure rather than composition, using small inhomogeneities to create effective macroscopic behavior.

♤ Negative refractive index of the metamaterials appear to permit the creation of superlenses which can have a spatial resolution below that of the wavelength.

♤ Potential applications of metamaterials are diverse and include remote aerospace applications, sensor detection and infrastructure monitoring, smart solar power management, public safety, radomes, high- frequency battlefield communication and lenses for high-gain antennas, improving ultrasonic sensors, and even shielding structures from earthquakes.

♤ The research in metamaterials is interdisciplinary and involves such fields as electrical engineering, electromagnetics, solid state physics, microwave and antennae engineering, optoelectronics, classic optics, material sciences, semiconductor engineering, nanoscience and others.