Proposal Number: ECS-9630068 Principal Investigator: Joseph Haus Title: Pulse Propagation in Periodic Dielectric Materials Analysis: In this research, electromagnetic wave propagation in photonic band gap (PBG) structures, containing new materials with both strong nonlinear absorption and nonlinear refraction, will be theoretically and experimentally investigated. In a photonic band gap structure, a periodic array introduces optically forbidden bands in analogy with electronic band gaps in solid state crystals. With the introduction of materials with a strong nonlinear refraction into a PBG system, it is expected that additional PBG effects will be introduced, which can also be controlled. Introduction of materials with a strong nonlinear reverse saturable absorption, into channels should result in a structure in which the optical response is limited in intensity by the material and by the diffraction and scattering properties of the photonic crystal. There are many applications for such structures in any situation in which intense light is a problem. The PBG structures in this investigation will be broad band to provide wavelength agile protection and will be capable of operating with a wide field of view. A strong direct experimental collaboration with researchers at the Naval Research Laboratory (NRL) has been established. The NRL component of the research will be funded by the Army Research Office (ARO), through NSF, via subcontract with Renssalear Polytechnic Institute. A copy of the ARO Augmentation Award Statement of Work defining the NRL research contribution, and the ARO reviews, are attached. The theoretical investigation at RPI is directly coupled to the experimental realization at NRL.
