Guest Editorial

ANEW paradigm has emerged, in which the band structureconcepts of solid-state physics are applied to electromag-netics. This has led to a profusion of scientific creativity as new forms of electromagnetic crystal structures are invented for radio and microwaves, as well as for optical wavelengths. These new structures are inspired by the three-dimensional (3-D) geometry of both natural crystals and those artificial crystals that can arise only in the human imagination. These artificial electromagnetic crystals (also known as photonic crystals) are impacting the diverse domains of elec-tromagnetics, extending from radio waves to optical wave-lengths. They are bringing together, under a common umbrella, scientists in the fields of classical electromagnetics, solid-state band theory, semiconductor device physics, quantum optics, nanostructures, and materials science. The number of papers in this field has been growing at roughly 70 % per year sinc