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

Nonlocal interferometry with high-intensity fields

J. D. Franson

Published Dec 1, 1993• 3 citations
Publisher

Abstract

Two-photon interferometry can produce violations of Bell's inequality that demonstrate the nonlocal nature of such effects. It is shown here that high-intensity fields containing large numbers of photons can violate Bell's inequality in a similar manner. The macroscopic nature of these fields is evident from the fact that they can produce large bursts of energy in two distant absorbers with nonlocal correlations between the two.

DOI
10.1103/physreva.48.4610

Related papers

Two-photon interferometry over large distances

J. D. Franson

Two correlated photons incident upon two distant interferometers can produce a coincidence rate that depends nonlocally on the sum of the phases of the interferometers. This effect has been observed for the case in which the optical path length between the two interferometers was 102 m. The results of the experiment are in good agreement with the quantum theory predictions and violate a recently derived inequality for semiclassical field theories.

Physical Review A•Oct 1, 1991•91 citations

Nonlocal interferometry using macroscopic coherent states and weak nonlinearities

Brian T. Kirby, J. D. Franson

A method for performing nonlocal interferometry using phase-entangled macroscopic coherent states is described. The required entanglement can be generated using weak nonlinearities while Bell's inequality can be violated using single photons as a probe. The entanglement is relatively robust against photon loss and Bell's inequality can be violated over a relatively large distance in optical fibers despite the fact that a large number of photons are absorbed in the process.

arXiv:1207.5487•Physical Review A•May 17, 2013•39 citations

Nonlocal photon correlations and violation of Bell inequalities for spatially separated classical light fields

Daniel Bhatti, Schneider, Raimund, Thomas Mehringer +2 more

It is theoretically and experimentally shown that photons emitted by statistically independent incoherent classical light sources and measured in the far field in spatially separated modes may display spatial correlations akin to path-entanglement of photons produced by quantum sources. By measuring higher order photon-correlations at different locations, i.e., $m$ photons in one mode and one photon in another mode, we experimentally demonstrate for $m \geq 6$ a violation of Bell-type inequalities for spatial degrees of freedom. The spatial correlations among the photons can be understood from state projection where the detection of the first $m$ photons projects the sources onto a state which emits the subsequent photon in a strongly correlated manner. From this perspective the entanglement and violation of Bell's inequalities appears as a consequence of nonvanishing cross correlations between noncommuting quadrature phase components of the two spatially separated fields after $m$ photons have been recorded. In this way we show that classical systems may produce spatial field correlations violating local realistic theories.

arXiv:1501.05351•Jan 21, 2015•0 citations

On production and detection of entanglement

Marek Żukowski

Progress in multiphoton interferometry allows us now to observe even six-photon interference of a very high contrast. Also, it is possible to observe interference of two photons originating from truly independent sources. Non-classical effects may violate Bell inequalities, or reveal quantum non-separability. Methods of producing non-classical states of few photons, and the detection of entanglement via Bell inequalities, or via nor-separability criteria will be presented. Implications of violations of Bell inequalities will be discussed, with a special stress on over-interpretations of this fact.

Optics and Spectroscopy•Feb 1, 2010•0 citations

Phase-sensitive tests of nonlocality of quantum-mechanical fields

Sze N. Tan, Murray Holland, Daniel F. Walls

Nonlocal effects associated with quantum-mechanical states have been theoretically interesting because they emphasize the differences between classical and quantum mechanics. We describe a system in which a single input photon causes a nonlocal influence on two spatially separated homodyne detectors, as evidenced by a violation of Bell's inequalities. Unlike previous configurations for violating Bell's inequalities, the correlation is not imposed on a pair of particles that spatially separate before being detected. Rather, the correlation arises from the interaction of the local oscillators at each homodyne detector with the spatially extended field of the input photon. The above effect is only one of a class of situations in which nonlocal correlations can be imposed on separated homodyne detectors by quantum mechanical fields. By deriving the conditions for violating Bell's inequality with phase-sensitive detectors, new tests can be developed that relate to squeezed light and other nonclassical fields.

Annual Meeting Optical Society of America•Jan 1, 1990•0 citations

Nonlocal Interferometry Using Schrodinger Cats

J. D. Franson

A method for performing nonlocal interferometry using macroscopic phase-entangled coherent states is described. This allows Bell’s inequality to be violated using Schrodinger cat states over relatively large distances in optical fibers.

The Rochester Conferences on Coherence and Quantum Optics and the Quantum Information and Measurement meeting•Jan 1, 2013•0 citations
Two-photon interferometry can produce violations of Bell's inequality that demonstrate the nonlocal nature of such effects. It is shown here that high-intensity fields containing large numbers of photons can violate Bell's inequality in a similar manner. The macroscopic nature of these fields is evident from the fact that they can produce large bursts of energy in two distant absorbers with nonlocal correlations between the two.
It is theoretically and experimentally shown that photons emitted by statistically independent incoherent classical light sources and measured in the far field in spatially separated modes may display spatial correlations akin to path-entanglement of photons produced by quantum sources. By measuring higher order photon-correlations at different locations, i.e., mmm photons in one mode and one photon in another mode, we experimentally demonstrate for m≥6m \geq 6m≥6 a violation of Bell-type inequalities for spatial degrees of freedom. The spatial correlations among the photons can be understood from state projection where the detection of the first mmm photons projects the sources onto a state which emits the subsequent photon in a strongly correlated manner. From this perspective the entanglement and violation of Bell's inequalities appears as a consequence of nonvanishing cross correlations between noncommuting quadrature phase components of the two spatially separated fields after mmm photons have been recorded. In this way we show that classical systems may produce spatial field correlations violating local realistic theories.
Progress in multiphoton interferometry allows us now to observe even six-photon interference of a very high contrast. Also, it is possible to observe interference of two photons originating from truly independent sources. Non-classical effects may violate Bell inequalities, or reveal quantum non-separability. Methods of producing non-classical states of few photons, and the detection of entanglement via Bell inequalities, or via nor-separability criteria will be presented. Implications of violations of Bell inequalities will be discussed, with a special stress on over-interpretations of this fact.
Nonlocal effects associated with quantum-mechanical states have been theoretically interesting because they emphasize the differences between classical and quantum mechanics. We describe a system in which a single input photon causes a nonlocal influence on two spatially separated homodyne detectors, as evidenced by a violation of Bell's inequalities. Unlike previous configurations for violating Bell's inequalities, the correlation is not imposed on a pair of particles that spatially separate before being detected. Rather, the correlation arises from the interaction of the local oscillators at each homodyne detector with the spatially extended field of the input photon. The above effect is only one of a class of situations in which nonlocal correlations can be imposed on separated homodyne detectors by quantum mechanical fields. By deriving the conditions for violating Bell's inequality with phase-sensitive detectors, new tests can be developed that relate to squeezed light and other nonclassical fields.