Annual Meeting Optical Society of America

Compensation of phase distortions in conjugating media

Matthew C. Bashaw, Abraham Aharoni, Lambertus Hesselink

Published Jan 1, 1992• 0 citations

Abstract

Phase-conjugated light waves are known to reverse phase distortions in media with negligible absorption or for paraxial beam propagation.1 We examine here a different case in which a volume conjugating medium is itself imperfect, possessing phase distortions and a conjugating efficiency dependent on grating spatial frequency. We show theoretically that for multiplexed signals, cross-talk-free phase conjugation is obtained only for negligible spatial-frequency dispersion and a phase-conjugated reference wave. We further present experimental results in a severely striated sample of photorefractive strontium barium niobate; using a phase-conjugated reference wave, we demonstrate the alleviation of distortion2 and the elimination of cross talk between closely spaced angularly multiplexed signals.

DOI: 10.1364/oam.1992.tuo7

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