Guiding Light Through Sharp Bends Using Two Dimensional Photonic Crystals

The current effort to make integrated optical chips requires guiding light around sharp corners with a radius of curvature on the order of a wavelength. Light propagates in conventional waveguides as a result of total internal reflection at the interface between the high-refractive index guiding layer and its low-index surroundings. However, bends in the conventional index-contrast waveguides are susceptible to large optical losses depending on the radius of curvature of the bend. These optical losses, due to radiation, can be avoided by using a Two-Dimensional (2D) photonic crystal.