Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Spatial entanglement of twin quantum images

Patrick Navez, E. Brambilla, A. Gatti, Luigi A. Lugiato

Published Dec 14, 2001• 27 citations
Publisher

Abstract

We show that the spatial entanglement of two twin images obtained by parametric down conversion is complete, i.e., concerns both amplitude and phase. By considering a homodyne detection scheme, which allows comparison of field quadrature components of the two images pixel by pixel, Einstein-Podolsky-Rosen correlations are shown to exist between symmetrical pixels of the two images. The best possible correlation is obtained by adjusting the phase profile of the local oscillator in the amplification area. The results for quadrature components hold even in the absence of any input image, i.e., for pure parametric fluorescence. In this case, they are not related to intensity and phase fluctuations.

DOI
10.1103/physreva.65.013813

Related papers

Spatial entanglement of twin quantum images

E. Brambilla, A. Gatti, Patrick Navez +1 more

We show that spatial entanglement of two twin images obtained by parametric down-conversion is complete, i.e. concerns both amplitude and phase. This is realised through a homodyne detection of these images which allows for measurement of the field quadrature components. EPR correlations are shown to exist between symmetrical pixels of the two images. The best possible correlation is obtained by adjusting the phase of the local oscillator field (LO) in the area of maximal amplification. The results for quadrature components hold unchanged even in absence of any input image i.e. for pure parametric fluorescence. In this case they are not related to intensity and phase fluctuations.

arXiv:quant-ph/0010108•Oct 30, 2000•0 citations

Quantum aspects of imaging

A. Gatti, E. Brambilla, Luigi A. Lugiato +1 more

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.

Journal of Optics B Quantum and Semiclassical Optics•Apr 1, 2000•15 citations

Spatial entanglement of twin quantum images

Patrick Navez, E. Brambilla, A. Gatti +1 more

Summary form only given. Optical system which display quantum entanglement properties in the spatial domain are of great interest for applications, since the amount of information that can be manipulated and processed in parallel exploiting quantum correlation effects increase substantially. In this paper, we consider the field generated through the process of frequency down-conversion in a travelling wave optical parametric amplifier. We present new results showing that the two images are locally correlated, not only with respect to intensity fluctuations, but also to phase fluctuations.

Conference on Lasers and Electro-Optics•Aug 29, 2005•0 citations

Einstein-Podolsky-Rosen Paradox in Twin Images

Paul‐Antoine Moreau, F. Devaux, Éric Lantz

Spatially entangled twin photons provide both promising resources for modern quantum information protocols, because of the high dimensionality of transverse entanglement, and a test of the Einstein-Podolsky-Rosen paradox in its original form of position versus impulsion. Usually, photons in temporal coincidence are selected and their positions recorded, resulting in a priori assumptions on their spatiotemporal behavior. In this Letter, we record, on two separate electron-multiplying charge coupled devices cameras, twin images of the entire flux of spontaneous down-conversion. This ensures a strict equivalence between the subsystems corresponding to the detection of either position (image or near-field plane) or momentum (Fourier or far-field plane). We report the highest degree of paradox ever reported and show that this degree corresponds to the number of independent degrees of freedom, or resolution cells, of the images.

arXiv:1404.3028•Physical Review Letters•Oct 14, 2014•104 citations

Quantum Entangled Images

A. Gatti, E. Brambilla, Luigi A. Lugiato +1 more

We analyze a scheme consisting of an optical parametric amplifier and two imaging lenses. From an off-axis input image such a system creates two quantum entangled output images, signal and idler, symmetrical with respect to the optical axis of the scheme. In the limit of large amplification the idler image is a quantum twin of the signal one in the sense that they display identical intensity fluctuations in space-time.

Physical Review Letters•Aug 30, 1999•92 citations

The Einstein-Podolsky-Rosen (EPR) paradox in single couples of images

Éric Lantz, Séverine Denis, Paul‐Antoine Moreau +1 more

Spatially entangled twin photons provide a test of the Einstein-Podolsky-Rosen (EPR) paradox in its original form of position (image plane) versus impulsion (Fourier plane). We show that recording a single pair of images in each plane is sufficient to safely demonstrate an EPR paradox. On each pair of images, we have retrieved the fluctuations by subtracting the fitted deterministic intensity shape and then have obtained an intercorrelation peak with a sufficient signal to noise ratio to safely distinguish this peak from random fluctuations. A 95% confidence interval has been determined, confirming a high degree of paradox whatever the considered single pairs. Last, we have verified that the value of the variance of the difference between twin images is always below the quantum (poissonian) limit, in order to ensure the particle character of the demonstration. Our demonstration shows that a single image pattern can reveal the quantum and non-local behavior of light.

•Sep 13, 2015•0 citations
We show that the spatial entanglement of two twin images obtained by parametric down conversion is complete, i.e., concerns both amplitude and phase. By considering a homodyne detection scheme, which allows comparison of field quadrature components of the two images pixel by pixel, Einstein-Podolsky-Rosen correlations are shown to exist between symmetrical pixels of the two images. The best possible correlation is obtained by adjusting the phase profile of the local oscillator in the amplification area. The results for quadrature components hold even in the absence of any input image, i.e., for pure parametric fluorescence. In this case, they are not related to intensity and phase fluctuations.
We show that spatial entanglement of two twin images obtained by parametric down-conversion is complete, i.e. concerns both amplitude and phase. This is realised through a homodyne detection of these images which allows for measurement of the field quadrature components. EPR correlations are shown to exist between symmetrical pixels of the two images. The best possible correlation is obtained by adjusting the phase of the local oscillator field (LO) in the area of maximal amplification. The results for quadrature components hold unchanged even in absence of any input image i.e. for pure parametric fluorescence. In this case they are not related to intensity and phase fluctuations.
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.
Summary form only given. Optical system which display quantum entanglement properties in the spatial domain are of great interest for applications, since the amount of information that can be manipulated and processed in parallel exploiting quantum correlation effects increase substantially. In this paper, we consider the field generated through the process of frequency down-conversion in a travelling wave optical parametric amplifier. We present new results showing that the two images are locally correlated, not only with respect to intensity fluctuations, but also to phase fluctuations.
Spatially entangled twin photons provide both promising resources for modern quantum information protocols, because of the high dimensionality of transverse entanglement, and a test of the Einstein-Podolsky-Rosen paradox in its original form of position versus impulsion. Usually, photons in temporal coincidence are selected and their positions recorded, resulting in a priori assumptions on their spatiotemporal behavior. In this Letter, we record, on two separate electron-multiplying charge coupled devices cameras, twin images of the entire flux of spontaneous down-conversion. This ensures a strict equivalence between the subsystems corresponding to the detection of either position (image or near-field plane) or momentum (Fourier or far-field plane). We report the highest degree of paradox ever reported and show that this degree corresponds to the number of independent degrees of freedom, or resolution cells, of the images.
Spatially entangled twin photons provide a test of the Einstein-Podolsky-Rosen (EPR) paradox in its original form of position (image plane) versus impulsion (Fourier plane). We show that recording a single pair of images in each plane is sufficient to safely demonstrate an EPR paradox. On each pair of images, we have retrieved the fluctuations by subtracting the fitted deterministic intensity shape and then have obtained an intercorrelation peak with a sufficient signal to noise ratio to safely distinguish this peak from random fluctuations. A 95% confidence interval has been determined, confirming a high degree of paradox whatever the considered single pairs. Last, we have verified that the value of the variance of the difference between twin images is always below the quantum (poissonian) limit, in order to ensure the particle character of the demonstration. Our demonstration shows that a single image pattern can reveal the quantum and non-local behavior of light.