Sub-nanosecond optical switch based on silicon racetrack resonator

We experimentally demonstrate a small-size and high-speed silicon optical switch based on the free carrier plasma dispersion in silicon.Using an embedded racetrack resonator with a quality factor of 7400,the optical switch shows an extinction ratio exceeding 13 dB with a footprint of only 2.2×10mm~2.Moreover,a novel pre-emphasis technique is introduced to improve the optical response performance and the rise and the fall times are reduced down to 0.24 ns and 0.42 ns respectively,which are 25%and 44%lower than those without the pre-emphasis.