Photonic Crystal Chip-scale Optical Networks

Two-dimensional planar photonic crystal technology offers the potential for compact optical signal routing and processing while realizing the advantages of massive parallelism through optical interconnection, low skew clock distribution, and resistance to electromagnetic interference. What has limited this potential to date is the enormous loss associated with current techniques in realizing single-mode structures in high index contrast dielectric materials. We propose a hybrid technique based upon standard low index contrast dielectric integrated optics technology where high index dielectric, semiconductor, or metallic inclusions are embedded at appropriate locations where photonic crystal based components are needed. This technique relies on chemical-mechanical planarization to maintain both vertical symmetry and vertical waveguide confinement, thereby minimizing out of plane scattering losses and diffraction losses, and can be readily extended to realize multi-level, three-dimensional optical circuitry. There are many commercial applications and markets for these functions that are traditionally implemented with high-cost free-space optics. The benefits of this research will be to make progress in terms of developing chip scale integration of all-optical components for optical systems employing photonic crystals to provide a variety of functions including guiding, switching, splitting, modulating, coupling and filtering.