A method for generating electromagnetic radiation, including the steps of: providing a series of adjacent electrode pairs arranged on a common dielectric substrate, the electrodes of each electrode pair substantially aligned on opposite sides of the common dielectric substrate; energizing a first electrode pair in the series of electrode pairs at an energizing time to produce a volume polarization distribution pattern within the common dielectric substrate; energizing a next adjacent electrode pair in the series of adjacent electrode pairs at a next energizing time to produce a variation of the volume polarization distribution pattern within the common dielectric substrate, the center of the next adjacent electrode pair located a distance from the center of the previous adjacent electrode pair, wherein the next energizing time is a time interval after the previous energizing time, the time interval less than the time for light to travel the distance between the centers of the previous and the next adjacent electrode pairs; and repeating the step of energizing the next adjacent electrode pair for subsequent electrode pairs in the series of adjacent electrode pairs to produce a continuous time-varying volume polarization distribution pattern within the common dielectric substrate.