Fidelity-threshold and critical slowing down in photorefractive double phase conjugate mirrors

Summary form only given. In conclusion, we present theoretical and experimental results that analyze the double phase conjugation process. We establish the existence of gain-threshold and point out the differences between conjugation fidelity and conjugation reflectivity. We study the oscillatory nature of the DPCM and predict the existence of critical slowing down near the gain-threshold.<
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