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Applications Of Photonic Band Gap Structures

Henry O. Everitt

Imagine a material that would exclude all electromagnetic radiation in 4π steradians over a range of frequencies. The center frequency of the exclusion gap could be determined by the experimenter to be anywhere from the optical to the microwave region. The width of the gap would be large, at least 20% of the center frequency. Radiation outside that gap would be transmitted through the material, while radiation in the gap would be reflected. In-gap radiation generated inside the material would be trapped. Uses for such a material would be manifold, from filtering and noise suppression to modification of the electromagnetic vacuum and suppression of spontaneous emission. Such a material has recently been created: the photonic band gap crystal.