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Journal of Optics B Quantum and Semiclassical Optics

Quantum aspects of imaging

A. Gatti, E. Brambilla, Luigi A. Lugiato, Mikhail I. Kolobov

Published Apr 1, 2000• 15 citations
Publisher

Abstract

Nonclassical spatial correlations are shown to arise in the cross section of transverse multimode optical beams as a consequence of nonlinear wave mixing phenomena. These correlations represent a macroscopic manifestation of quantum entanglement. As an applicative perspective, we discuss some quantum aspects of parametric amplification of images. A broadband parametric amplifier, enclosed in a telescopic system, is able to amplify and duplicate a faint coherent image. We show that the two output images are quantum twins of each other, in the sense that intensity fluctuations in corresponding pixels are correlated with a conditional variance well beyond the standard quantum limit. In a phase-sensitive amplification scheme we demonstrate an efficient transfer of information from the input image to each of the two output images.

DOI
10.1088/1464-4266/2/2/323

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