Cited by 432Quantum Information and CryptographyQuantum Computing Algorithms and ArchitectureQuantum optics and atomic interactions

The DOI matches its Crossref record; 59 of the 59 references it cites were found in a registry or an index; none of the 18 sources its claims cite is checked for support yet.

12-Photon Entanglement and Scalable Scattershot Boson Sampling with Optimal Entangled-Photon Pairs from Parametric Down-Conversion

Open access

Abstract

Entangled-photon sources with simultaneously near-unity heralding efficiency and indistinguishability are the fundamental elements for scalable photonic quantum technologies. We design and realize a degenerate telecommunication wavelength entangled-photon source from an ultrafast pulsed laser pumped spontaneous parametric down-conversion (SPDC), which shows simultaneously 97% heralding efficiency and 96% indistinguishability between independent single photons without narrow-band filtering. Such a beamlike and frequency-uncorrelated SPDC source allows generation of the first 12-photon genuine entanglement with a state fidelity of 0.572±0.024. We further demonstrate a blueprint of scalable scattershot boson sampling using 12 SPDC sources and a 12×12 mode interferometer for three-, four-, and five-boson sampling, which yields count rates more than 4 orders of magnitude higher than all previous SPDC experiments.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

The paper reports an optimized ultrafast-pumped SPDC entangled-photon source with simultaneously near-unity heralding efficiency and indistinguishability, enabling the first 12-photon genuine entanglement and a scalable scattershot boson sampling blueprint. Using 12 SPDC sources and a 12×12-mode interferometer, it demonstrates three-, four-, and five-boson sampling with multi-photon count rates more than four orders of magnitude higher than previous SPDC experiments.

Key findings

  • The source achieved ~97% corrected heralding efficiency and ~96% indistinguishability between independent single photons; Hong-Ou-Mandel interference showed a raw visibility of 0.962 ± 0.011, spectral purity was 0.99, and Bell-state visibility was above 0.997.
  • The first 12-photon genuine entanglement was generated with population P = 0.732 ± 0.024, coherence C = 0.419 ± 0.041, and state fidelity reported as 0.572 ± 0.024 in the abstract (0.576 ± 0.024 in the main text), exceeding the 0.5 threshold by more than 3 standard deviations.
  • Scattershot boson sampling with 12 SPDC sources and a 12×12-mode interferometer measured three-, four-, and five-photon sampling rates of 3.9 kHz, 44 Hz, and 0.3 Hz, respectively; the 3-boson sampling gave similarity 0.982 ± 0.004 and distance 0.122 ± 0.018.
  • The 3.9 kHz three-photon count rate is more than four orders of magnitude higher than the best previous SPDC-based boson sampling experiments and comparable to state-of-the-art quantum-dot single-photon work.

Methods

  • The entangled-photon source used beam-like type-II SPDC in a 6.3-mm BBO crystal pumped by a 775-nm pulsed laser with 5.5-nm bandwidth and 80-MHz repetition, generating photon pairs around 1550 nm; YVO4 beam displacers, half-wave plates, dispersion-compensating prisms, 30-nm bandpass filters, and superconducting nanowire single-photon detectors with ~75% average efficiency were used.
  • For 12-photon entanglement, six BBO crystals produced six entangled pairs; one photon from each pair was combined on five polarization beam splitters, and 12-photon coincidences were post-selected and measured with wave plates, PBSs, and 24 SNSPDs at 1.8 W pump power and 0.55-mm focal waist, giving a 2.0 MHz two-photon rate and about one 12-photon coincidence per hour.
  • For scattershot boson sampling, 12 SPDC sources fed a 12×12-mode interferometer encoded in spatial and polarization modes; idler photons heralded signal photons, and the experiment used a 0.8-mm pump waist and 0.5 MHz two-photon count rate, with similarity/distance metrics and likelihood ratio tests against a distinguishable-photon hypothesis.

Limitations

  • The paper states that scaling to larger photon numbers is prohibited by the intrinsically probabilistic generation of entangled photon pairs in SPDC, which would require multiplexing.
  • The paper states that similarity/distance characterization is not scalable to larger photon numbers; for four- and five-boson sampling the input-output combinations reach 495×495 and 792×792, making counting events extremely scarce, so a likelihood ratio test was used instead.
  • The paper notes that the slight deviation of the measured HOM visibility from the predicted 0.99 could be caused by residual dispersion of the pump laser; the text also makes evident that the 12-photon coincidence rate was about one per hour and the five-boson sampling rate was 0.3 Hz.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1103/physrevlett.121.250505

Cites

59 of 59 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

0 of 18 cited sources checked · 0 supported · 0 flagged

Show all 31 claims

  • It may state two separate claims as one. 6
  • Probably not a substantial claim. 5
11 of 11
  • The paper relies on this without support.

    Near-unity heralding efficiency and indistinguishability are fundamental requirements for scalable photonic quantum technologies.

    “Entangled photon sources with simultaneously near-unity heralding efficiency and indistinguishability are the fundamental elements for scalable photonic quantum technologies.”
  • The paper relies on this without support.

    The lack of a perfect entangled-photon source is the main reason scalable multi-photon entanglement remained challenging.

    “Yet, a more scalable implementation remained challenging, largely to the lack of a perfect entangled-photon source produced by ultrafast laser pumped SPDC where the photonic entanglement fidelity, the collection efficiency, and the indistinguishability between independent photons are simultaneously engineered to close to unity.”
  • The paper relies on this without support.

    The simultaneous combination of near-unity entanglement fidelity, indistinguishability, and collection efficiency remained an outstanding goal before this work.

    “There has been important progress in preparing heralded single photons in frequencyuncorrelated pure quantum state [42][43][44], yet the simultaneous combination of nearunity entanglement fidelity, indistinguishability, and collection efficiency remained an outstanding goal.”
3 of 3

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Hong-Ou-Mandel citation points to the wrong reference

    Minor

    The text cites reference 47 for Hong-Ou-Mandel interference, but the bibliography lists the Hong, Ou, and Mandel paper as reference 46; reference 47 is a different paper.

1 of 1

Citations

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. 10.4086/toc.2013.v009a004 · DOI

Cited by

Sorted by citations

See all 432

Metadata

Authors
Zhong, H.-S., Li, Y., Li, W., Peng, L.-C., Su, Z.-E., Hu, Y., He, Y.-M., Ding, X., Zhang, W., Li, H., Zhang, L., Wang, Z., You, L., Wang, X.-L., Jiang, X., Li, L., Chen, Y.-A., Liu, N.-L., Lu, C.-Y., & Pan, J.-W.
Affiliations
  • University of Science and Technology of China (CN)
  • Chinese Academy of Sciences (CN)
Venue
Physical Review Letters
Published
2018-12-21
Volume
121
Issue
25
Pages
250505-250505
ISSN
  • 0031-9007 (ISSN-L)
  • 1079-7114
OpenAlex
W2896439086
Cited by
432
References
59
Citations by year
2026: 45 · 2025: 54 · 2024: 60 · 2023: 56 · 2022: 58 · 2021: 59 · 2020: 62 · 2019: 35 · 2018: 3
FWCI
18.86
Type
journal article
Language
en
Open access
Locations
  • Physical Review Letters (publishedVersion)
  • PubMed (publishedVersion)
  • arXiv (Cornell University) (submittedVersion)
  • Figshare (submittedVersion, cc-by)
  • arXiv (Cornell University)
  • Bulletin of the American Physical Society
Funders
  • National Natural Science Foundation of China (91836303)
  • Chinese Academy of Sciences
  • National Fundamental Research Program
Topics
  • Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum Information and Cryptography
  • Physical Sciences › Computer Science › Artificial Intelligence › Quantum Computing Algorithms and Architecture
  • Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum optics and atomic interactions
Keywords
entangled photon pairs, spontaneous parametric down-conversion, heralding efficiency, photon indistinguishability, photonic quantum technologies

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

A language model drew the claims from the paper on 2026-11-10, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).

A second model labelled each claim on 2026-11-10 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review