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

Quantum 2.0 Conference and Exhibition

Structured near-field spatial correlations in entangled photons

Radhika Prasad, Sanjana Wanare, Suman Karan, Mritunjay K. Joshi, Abhinandan Bhattacharjee, Anand K. Jha

Published Jan 1, 2023• 0 citations
Publisher

Abstract

Structured correlations are important for quantum imaging. We propose and experimentally demonstrate a method to structure spatial two-photon correlations in the near-field by controlling phase-matching. Entanglement witnessed in the near-field enables these structured two-photon correlations to be useful for entanglement-based applications.

DOI
10.1364/quantum.2023.qth2a.26

Related papers

Structuring two-photon correlation of entangled field: experimental demonstration

Radhika Prasad, Sanjana Wanare, Suman Karan +3 more

Structured correlations are important for quantum imaging. We propose and experimentally demonstrate a method to structure spatial two-photon correlations in the near-field by controlling phase-matching. Entanglement witnessed in the near-field enables these structured two-photon correlations to be useful for entanglement-based applications.

Frontiers in Optics•Jan 1, 2023•0 citations

Structured position-momentum-entangled two-photon fields

Radhika Prasad, Sanjana Wanare, Suman Karan +3 more

Structured optical fields have led to several ground-breaking techniques in classical imaging and microscopy. At the same time, in the quantum domain, position-momentum entangled photon fields have been shown to have several unique features that can lead to beyond-classical imaging and microscopy capabilities. Therefore, it is natural to expect that position-momentum entangled two-photon fields that are structured can push the boundaries of quantum imaging and microscopy even further beyond. Nonetheless, the existing experimental schemes are able to produce either structured two-photon fields without position-momentum entanglement, or position-momentum entangled two-photon fields without structured correlations. In this article, by manipulating the phase-matching condition of the spontaneous parametric down-conversion process, we report experimental generation of two-photon fields with various structures in their spatial correlations. We experimentally measure the minimum bound on the entanglement of formation and thereby verify the position-momentum entanglement of the structured two-photon field. We expect this work to have important implications for quantum technologies related to imaging and sensing.

arXiv:2412.10954•Physical Review Applied•Dec 10, 2024•5 citations

Engineering of two-photon spatial quantum correlations behind a double slit

Wouter H. J. Peeters, J. J. Renema, Martin P. van Exter

This paper demonstrates the engineering of spatially entangled two-photon states behind a double slit by tailoring the incident pure two-photon state. We experimentally characterize many different two-photon states by measuring their complete two-photon interference patterns in the far field of the double slit. Spatial entanglement right behind the double slit can reside in either the modulus or the phase of the two-photon field. The balance between these two types of entanglement is fully controlled by experimentally utilizing the phase-front curvatures of the pump beam and the phase-matching profile. We project either a far-field image or a magnified near-field image of the two-photon source onto the double slit. Our theoretical analysis shows how the two-photon interference pattern behind the double slit effectively acts as a phase-sensitive probe of the incident two-photon field profile. We thus present phase-sensitive measurements of the generated two-photon field profile probed in an image plane of the two-photon source.

Physical Review A•Apr 16, 2009•60 citations

Manipulating spatial structure of high-order quantum coherence with entangled photons

Shuang‐Yin Huang, Gao, Jing, Zhi‐Cheng Ren +10 more

High-order quantum coherence reveals the statistical correlation of quantum particles. Manipulation of quantum coherence of light in temporal domain enables to produce single-photon source, which has become one of the most important quantum resources. High-order quantum coherence in spatial domain plays a crucial role in a variety of applications, such as quantum imaging, holography and microscopy. However, the active control of high-order spatial quantum coherence remains a challenging task. Here we predict theoretically and demonstrate experimentally the first active manipulation of high-order spatial quantum coherence by mapping the entanglement of spatially structured photons. Our results not only enable to inject new strength into current applications, but also provide new possibilities towards more wide applications of high-order quantum coherence.

arXiv:2306.00772•Jun 1, 2023•0 citations

Observation of near-field correlations in spontaneous parametric down-conversion

H. Di Lorenzo Pires, Martin P. van Exter

We experimentally demonstrate how the two-photon field generated by spontaneous parametric down-conversion contains an intriguing fine structure associated with the positional spread within the photon pair. The obtained results provide a three-dimensional picture of the near-field correlations, which are determined by the phase-matching conditions. These correlations are compared with previous results on second-harmonic generation, spatial antibunching, and transverse entanglement in parametric down-conversion.

Physical Review A•Apr 3, 2009•15 citations

Control of quantum coherence of photons exploiting quantum entanglement

Dianzhen Cui, Xi‐Lin Wang, X. X. Yi +1 more

Accurately controlling the quantum coherence of photons is pivotal for their applications in quantum sensing and quantum imaging. Here, we propose the utilization of quantum entanglement and local phase manipulation techniques to control the higher-order quantum coherence of photons. By engineering the spatially varying phases in the transverse plane, we can precisely manipulate the spatial structure of the second-order coherence function of entangled photon pairs without changing the photon intensity distribution of each photon. Our approach can readily be extended to higher-order quantum coherence control. These results could potentially stimulate experimental research and applications of optical quantum coherence.

arXiv:2305.19825•Physical Review Applied•Feb 9, 2024•5 citations
Structured correlations are important for quantum imaging. We propose and experimentally demonstrate a method to structure spatial two-photon correlations in the near-field by controlling phase-matching. Entanglement witnessed in the near-field enables these structured two-photon correlations to be useful for entanglement-based applications.
Structured optical fields have led to several ground-breaking techniques in classical imaging and microscopy. At the same time, in the quantum domain, position-momentum entangled photon fields have been shown to have several unique features that can lead to beyond-classical imaging and microscopy capabilities. Therefore, it is natural to expect that position-momentum entangled two-photon fields that are structured can push the boundaries of quantum imaging and microscopy even further beyond. Nonetheless, the existing experimental schemes are able to produce either structured two-photon fields without position-momentum entanglement, or position-momentum entangled two-photon fields without structured correlations. In this article, by manipulating the phase-matching condition of the spontaneous parametric down-conversion process, we report experimental generation of two-photon fields with various structures in their spatial correlations. We experimentally measure the minimum bound on the entanglement of formation and thereby verify the position-momentum entanglement of the structured two-photon field. We expect this work to have important implications for quantum technologies related to imaging and sensing.
This paper demonstrates the engineering of spatially entangled two-photon states behind a double slit by tailoring the incident pure two-photon state. We experimentally characterize many different two-photon states by measuring their complete two-photon interference patterns in the far field of the double slit. Spatial entanglement right behind the double slit can reside in either the modulus or the phase of the two-photon field. The balance between these two types of entanglement is fully controlled by experimentally utilizing the phase-front curvatures of the pump beam and the phase-matching profile. We project either a far-field image or a magnified near-field image of the two-photon source onto the double slit. Our theoretical analysis shows how the two-photon interference pattern behind the double slit effectively acts as a phase-sensitive probe of the incident two-photon field profile. We thus present phase-sensitive measurements of the generated two-photon field profile probed in an image plane of the two-photon source.
High-order quantum coherence reveals the statistical correlation of quantum particles. Manipulation of quantum coherence of light in temporal domain enables to produce single-photon source, which has become one of the most important quantum resources. High-order quantum coherence in spatial domain plays a crucial role in a variety of applications, such as quantum imaging, holography and microscopy. However, the active control of high-order spatial quantum coherence remains a challenging task. Here we predict theoretically and demonstrate experimentally the first active manipulation of high-order spatial quantum coherence by mapping the entanglement of spatially structured photons. Our results not only enable to inject new strength into current applications, but also provide new possibilities towards more wide applications of high-order quantum coherence.
We experimentally demonstrate how the two-photon field generated by spontaneous parametric down-conversion contains an intriguing fine structure associated with the positional spread within the photon pair. The obtained results provide a three-dimensional picture of the near-field correlations, which are determined by the phase-matching conditions. These correlations are compared with previous results on second-harmonic generation, spatial antibunching, and transverse entanglement in parametric down-conversion.
Accurately controlling the quantum coherence of photons is pivotal for their applications in quantum sensing and quantum imaging. Here, we propose the utilization of quantum entanglement and local phase manipulation techniques to control the higher-order quantum coherence of photons. By engineering the spatially varying phases in the transverse plane, we can precisely manipulate the spatial structure of the second-order coherence function of entangled photon pairs without changing the photon intensity distribution of each photon. Our approach can readily be extended to higher-order quantum coherence control. These results could potentially stimulate experimental research and applications of optical quantum coherence.