Utilizing interband and intraband processes in QD-SOAs for controlling the light velocity

Physical processes in semiconductor optical amplifiers (SOAs) are discussed for the purpose of controlling the velocity of light. For all-optical networking applications, control of velocity of light at bandwidths greater than 100 Gb/s is required. Using interband and ultra-fast intraband nonlinear processes, including spectral hole burning and carrier heating, present in SOAs enables the control of optical signals ranging from 1 GHz to larger than 1 THz. The rate equations for intraband effects are derived and utilized to control optical signals at THz bandwidth. Both optical and electrical control of phase shifts is obtained. An advance bandwidth product of 10 is achieved by utilizing intraband effects in QD-SOA.