Photorefractive adaptive transmission system: all optical signal modulation and amplified phase conjugation

The operational principles of an adaptive transmitter system based on the combined action of two photorefractive crystals, an amplifier and a phase conjugator have been presented. The system is capable of generating amplified, phase-modulated, phase-conjugate signals of low-intensity probe signal fields. The generation of amplified PC replicas is seen to be limited to within a specific range of low input signal intensities. This coincides with a useful region in which efficient optical phase modulation at frequencies greatly exceeding the characteristic response of the PR materials can be performed. The overall system is seen to preserve its real time phase-conjugation behavior and can thus be characterised as an all-optical adaptive transmission system