Light localization for broadband integrated optics in three dimensions

We demonstrate a universal mechanism for high-bandwidth, lossless, subwavelength scale circuitry in a fully three-dimensional (3D) all-optical microchip. Here light is confined and guided in air by wave interference, rather than total internal reflection. Our 3D circuit design consists of several planar microchip layers linked by vertical waveguides. The 3D microchip enables up to 200 nm single-mode waveguiding in each planar chip layer and 100 nm bandwidth chip-to-chip interconnects in a variety of 3D photonic band gap materials.