Active and applied functional rf metamaterials
The concept of electromagnetic metamaterials, defined here as artificial materials that are designed to obtain specific effective electromagnetic material properties, has revolutionized thinking about wave behavior in materials and the design of complex electromagnetic devices.Although originally conceived in passive form, the concept of electromagnetic metamaterials is applicable to more complicated structures. Why not embed into metamaterials circuit behavior that is more complicated than what one can obtain from linear, time-invariant, passive circuit elements? What kinds of new and interesting and potentially useful behavior can one obtain? These are the fundamental questions that have motivated the research described in this chapter. Our focus here is on the integration of complex functionality into metamaterials using powered and/or nonlinear elements.