Photonic-Crystal-Based Chip-Scale Optical Integration

Ultrasmall and ultra-high-Q optical cavities have been realized in photonic-crystal slabs, which have a number of exceptional features hardly available in other media. These cavities have been applied to all-optical switches and bistable memories in a Si photonic-crystal chip. They are integratable in a small chip and consume extremely small energies. We discuss their potential for on-chip optical integration and digital photonics application, and also describe novel functionalities arising from dynamic tuning of nanocavities.