Photonic-chip-based tunable slow and fast light via stimulated Brillouin scattering

We report the first (to our knowledge) demonstration of photonic chip based tunable slow and fast light via stimulated Brillouin scattering. Slow, fast, and negative group velocities were observed in a 7 cm long chalcogenide (As2S3) rib waveguide with a group index change ranging from similar to-44 to +130, which results in a maximum delay of similar to 23 ns at a relatively low gain of similar to 23 dB. Demonstration of large tunable delays in a chip scale device opens up applications such as frequency sensing and true-time delay for a phased array antenna, where integration and delays similar to 10 ns are highly desirable. (C) 2012 Optical Society of America