Compact silicon-based integrated optic time delays

We demonstrate a 3-b (eight-channel) guided-wave optical delay line network in the silicon-on-insulator (SOI) waveguide technology with an incremental time delay of 12.3 ps measured over 2-20-GHz frequency range. The high-refractive index (compared to silica) combined with tight optical confinement and low propagation loss in the SOI waveguide enables us to realize a compact time-delay network with fine resolution time delays necessary in a high-frequency phased-array antenna.