Continuously-tunable, bit-rate variable OTDM using broadband SBS slow-light delay line

We conceptually compare the advantages of the proposed slow-light-based tunable OTDM to conventional fiber-based fixed OTDM multiplexer. We experimentally demonstrate continuously-controllable OTDM of two 2.5-Gb/s return-to-zero (RZ) signals using broadband SBS-based slow-light as the tunable optical delay line. We show that the time slot of one signal path can be manipulated relative to the other by as much as 75-ps. This continuous slow light tunability dramatically enhances the OTDM system performance which results in a power penalty reduction of 9-dB for the multiplexed data stream. We also demonstrate variable-bit-rate OTDM by dynamically adjusting the tunable slow-light delay according to the input bit-rates. We show efficient two-by-one optical time multiplexing of three different input data streams at 2.5-Gb/s, 2.67-Gb/s and 5-Gb/s.