Electronics Letters · 2005 · 107 citations · 6 references
EngineeringElectrical EngineeringOptoelectronicsPhotonicsSemiconductor DevicesOptical AmplifiersOptical ModulationOptical Properties Of SemiconductorsOptical Signal ProcessingSemiconductor HeterostructuresSemiconductor PhysicsAll-optical LogicBoolean FunctionsCross-gain ModulationExtinctionExtinction RatioOptical Gain In SemiconductorsOptical Logic GatesSemiconductor Optical Amplifiers
By using gain nonlinearity characteristics of a semiconductor optical amplifier, an all-optical NAND gate at 10 Gbit/s is demonstrated. The all-optical NAND gate operates in single mechanism, which is cross-gain modulation. In the NAND gate (AB̄+Ā), Boolean AB̄ is obtained by using signal A as a probe beam and signal B as a pump beam in SOA-1. Also, Boolean Ā is obtained by using the clock signal as a probe beam and signal A as a pump beam in SOA-2. By adding the two outputs from SOA-1 and SOA-2, Boolean Ā+AB̄ (logic NAND) can be acquired. The extinction ratio is about 6.1 dB.
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