Modification of Planck blackbody radiation by photonic band-gap structures

Summary form only given. One of the most interesting subfields of quantum optics is cavity QED - where microcavities impose nontrivial boundary conditions on the quantized electromagnetic field and alter the matter-light interactions of quantum electrodynamics. One of the first predictions of this theory was the modification of atomic spontaneous emission rates, through the use of microcavities to alter the optical density of modes from its free-space value. This phenomenon is often known as the Purcell effect. Since this prediction, many theoretical analyses as well as experimental confirmations of this effect have been performed. Since the imposition of nontrivial boundary conditions modifies the electromagnetic Green´s function, the Feynman diagrams for any QED process must be altered in a cavity, giving physical results that differ from those in free space. The author reviews some of the theory related to the calculation of thermal power spectrum. Then he discusses how a finite 2D or 3D PBG structure can be qualitatively studied using a 1D formalism, following a model originally developed by John and Wang (1991). In the context of this model, he computes the thermal power spectrum of a PBG filter in front of an emitting hot surface, as well as that of a heated PBG structure. The author produces a quantitative theory for studying the off-axis spectrum of 1D PBG structures of the DBR type.