Photonic-crystal-based resonant-cavity-enhanced detectors

Summary form only given. The coherent scattering and interference of electromagnetic (EM) waves in three-dimensional ordered structures lead to formation of forbidden bands in which the propagation of photons is not allowed. These three-dimensional structures, known as photonic bandgap (PBG) crystals, have recently received both theoretical and experimental attention. Recently, Ho et al. (1994) have proposed and demonstrated a layer-by-layer three-dimensional photonic crystal, with a full PBG in all directions. This structure was fabricated at smaller scales by conventional methods, and defects or cavities around the same geometry was also investigated. The electrical fields in such cavities are usually enhanced, and by placing active devices in such cavities, one can make the device benefit from the wavelength selectivity and the large enhancement of the resonant EM field within the cavity. This effect has already been used in optoelectronics to achieve novel devices such as resonant cavity enhanced (RCE) photodetectors and light emitting diodes. In the paper, we demonstrate the RCE effect by placing microwave detectors within the localized modes of photonic crystal defect structures. In our experiments, we used defect structures built around the layer-by-layer dielectric photonic crystal.