Photonic crystal nanocavities for efficient light confinement and emission

When combined with high index contrast slabs in which light can be efficiently guided, microfabricated two-dimensional photonic crystals provide us with the geometries needed to confine and concentrate light into extremely small volumes and to obtain very high field intensities. Fabrication of optical structures has now evolved to a precision which allows us to control light within such etched nanostructures. Sub-wavelength nano-optic cavities can be designed for efficient and flexible control over both emission wavelength and frequency, and nanofabricated optical waveguides can be used for efficient coupling of light between devices. The substantial reduction of the size of optical components leads to their integration in large numbers and the possibility to combine different functionalities on a single chip, much in the same way as electronic components have been integrated for improved multi-functionality of microchips. Here we describe the use of microfabricated periodic structures, photonic crystals, to define functional nano-optic cavities for efficient confinement and emission of light, which leads to the desire for miniaturization of optical devices.