Variable optical delays at 1.55   μ m using fast light in an InAs/InP quantum dash based semiconductor optical amplifier

Room temperature optical variable delays are demonstrated using InAs/InP quantum dash semiconductor optical amplifiers (SOAs) at 1.55 μ m . A microwave frequency modulated single optical beam allows to demonstrate fast light through the achievement of maximum optical delays of 136 ps at 250 MHz and ∼ 55 ps at 2 GHz by means of electrical control of the SOA bias current. The group index variation is attributed to enhanced nearly degenerate four wave mixing of this material system as well as population pulsation.