Quantum aspects of imaging

Ray LaPierre

Ryan S. Bennink, Sean J. Bentley, Robert W. Boyd +1 more

Coincidence, or ghost, imaging is a technique that uses two correlated optical fields to form an image of an object. In this work we identify aspects of coincidence imaging which can be performed with classically correlated light sources and aspects which require quantum entanglement. We find that entangled photons allow high-contrast, high-resolution imaging to be performed at any distance from the light source. We demonstrate this fact by forming ghost images in the near and far fields of an entangled photon source, noting that the product of the resolutions of these images is a factor of 3 better than that which is allowed by classical diffraction theory.

Mikhail I. Kolobov

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.

Robert W. Boyd, Ryan S. Bennink, Sean J. Bentley +3 more

Coincidence (ghost) imaging forms an image using photons that have never encountered the object. We present experimental results showing which aspects of this process result from quantum entanglement and which can be understood classically.

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