Integrated superlattices and metamaterials

Physics is built on the use of constitutive equations governed by the Random Phase Approximation to deal with cancellations resulting from space-time variations of the phase of waves. Special handling of phase becomes possible in engineered materials, such as domain formations and periodicity. When dealing with interactions involving superlattices as well as metamaterials, the phase of electron or electromagnetic waves can be exploited in numerous ways. Examples include systems with gain such as amplifiers and oscillators, as well as serving as passive impedance matching elements such as image formation with lenses.