Synthetic Structures with Parity-Time Symmetry

Parity-time (PT) symmetric wave mechanics is a rapidly developed field with applications in various areas of physics and mathematics. Although originally proposed in the framework of Quantum Field Theory, it was recently recognized to be a natural mathematical language necessary to describe novel wave transport phenomena in synthetic structures where balanced gain and loss mechanisms coexist. Examples of its successful implementation can be found in areas ranging from integrated photonics and electronic circuitry to antenna theory and meta-materials. The objective of this chapter is to highlight some of these successes, both in modeling and experimental implementations, of PT-symmetric optical and electronic systems.