Abstract
Entangled photons are a crucial resource for quantum communication and linear optical quantum computation. Unfortunately, the applicability of many photon-based schemes is limited due to the stochastic character of the photon sources. Therefore, a worldwide effort has focused on overcoming the limitation of probabilistic emission by generating two-photon entangled states conditioned on the detection of auxiliary photons. Here we present the first heralded generation of photon states that are maximally entangled in polarization with linear optics and standard photon detection from spontaneous parametric downconversion1. We use the downconversion state corresponding to the generation of three photon pairs, where the coincident detection of four auxiliary photons unambiguously heralds the successful preparation of the entangled state2. This controlled generation of entangled photon states is a significant step towards the applicability of a linear optics quantum network, in particular for entanglement swapping, quantum teleportation, quantum cryptography and scalable approaches towards photonics-based quantum computing3.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 12 print issues and online access
$209.00 per year
only $17.42 per issue
Rent or buy this article
Prices vary by article type
from$1.95
to$39.95
Prices may be subject to local taxes which are calculated during checkout




Similar content being viewed by others
References
Kwiat, P. G. et al. New high-intensity source of polarization-entangled photon pairs. Phys. Rev. Lett. 75, 4337–4341 (1995).
Śliwa, C. & Banaszek, K. Conditional preparation of maximal polarization entanglement. Phys. Rev. A 67, 030101 (2003).
Nielsen, M. A. & Chuang, I. L. Quantum Computation and Quantum Information (Cambridge Univ. Press, 2000).
Knill, E., Laflamme, R. & Milburn, G. A scheme for efficient quantum computation with linear optics. Nature 409, 46–52 (2001).
Pittman, T., Jacobs, B. & Franson, J. Probabilistic quantum logic operations using polarizing beam splitters. Phys. Rev. A 64, 062311 (2001).
O'Brien, J. L., Pryde, G. J., White, A. G., Ralph, T. C. & Branning, D. Demonstration of an all-optical quantum controlled-NOT gate. Nature 426, 264–267 (2003).
Pittman, T., Fitch, M., Jacobs, B. & Franson, J. Experimental controlled-NOT logic gate for single photons in the coincidence basis. Phys. Rev. A 68, 032316 (2003).
Gasparoni, S., Pan, J.-W., Walther, P., Rudolph, T. & Zeilinger, A. Realization of a photonic controlled-NOT gate sufficient for quantum computation. Phys. Rev. Lett. 93, 020504 (2004).
Kwiat, P., Mitchell, J., Schwindt, P. & White, A. Grover's search algorithm: an optical approach. J. Mod. Opt. 47, 257–266 (2000).
Prevedel, R. et al. High-speed linear optics quantum computing using active feed-forward. Nature 445, 65–69 (2007).
Tame, M. S. et al. Experimental realization of Deutsch's algorithm in a one-way quantum computer. Phys. Rev. Lett. 98, 140501 (2007).
Lu, C.-Y., Browne, D. E., Yang, T. & Pan, J.-W. Demonstration of a compiled version of Shor's quantum factoring algorithm using photonic qubits. Phys. Rev. Lett. 99, 250504 (2007).
Lanyon, B. P. et al. Experimental demonstration of a compiled version of Shor's algorithm with quantum entanglement. Phys. Rev. Lett. 99, 250505 (2007).
Walther, P. et al. Experimental one-way quantum computing. Nature 434, 169–176 (2005).
Kimble, H. The quantum internet. Nature 453, 1023–1030 (2008).
Michler, P. et al. A quantum dot single-photon turnstile device. Science 290, 2282–2285 (2000).
Kurtsiefer, C., Mayer, S., Zarda, P. & Weinfurter, H. Stable solid-state source of single photons. Phys. Rev. Lett. 85, 290–293 (2000).
Pittman, T. et al. Heralded two-photon entanglement from probabilistic quantum logic operations on multiple parametric down-conversion sources. IEEE J. Sel. Top. Quantum Electron. 9, 1478–1482 (2003).
Walther, P., Aspelmeyer, M. & Zeilinger, A. Heralded generation of multiphoton entanglement. Phys. Rev. A 75, 012313 (2007).
Kok, P. & Braunstein, S. Limitations on the creation of maximal entanglement. Phys. Rev. A 62, 064301 (2000).
Zhang, Q. et al. Experimental quantum teleportation of a two-qubit composite system. Nature Phys. 2, 678–682 (2006).
Wieczorek,W. et al. Experimental entanglement of a six-photon symmetric Dicke state. Phys. Rev. Lett. 103, 020504 (2009).
Prevedel, R. et al. Experimental realization of Dicke states of up to six qubits for multiparty quantum networking. Phys. Rev. Lett. 103, 020503 (2009).
Rådmark, M., Zukowski, M. & Bourennane, M. Experimental high fidelity six-photon entangled state for telecloning protocols. New J. Phys. 11, 103016 (2009).
Coffman, V., Kundu, J. & Wootters,W. K. Distributed entanglement. Phys. Rev. A 61, 052306 (2000)
Clauser, J. F., Horne, M. A., Shimony, A. & Holt, R. A. Proposed experiment to test local hidden-variable theories. Phys. Rev. Lett. 23, 880–884 (1969).
Horodecki, R., Horodecki, P. & Horodecki, M. Violating Bell ineqaulity by mixed spin–1/2 states: necessary and sufficient condition. Phys. Lett. A 200, 340–344 (1995).
Wagenknecht, C. et al. Experimental demonstration of a heralded entanglement Source. Nature Photon. (in the press).
James, D., Kwiat, P., Munro, W. & White, A. Measurement of qubits. Phys. Rev. A 64, 052312 (2001).
Hradil, Z. Quantum-state estimation. Phys. Rev. A 55, R1561–R1564 (1997).
Banaszek, K., D'Ariano, G. M., Paris, M. G. A. & Sacchi, M. F. Maximum-likelihood estimation of the density matrix. Phys. Rev. A 61, 010304 (1999).
Acknowledgements
The authors are grateful to R. Prevedel, X. Ma, M. Aspelmeyer, Č. Brukner and T. Pittman for discussions and G. Mondl for assistance with the electronics. This work was supported by the Austrian Science Fund (FWF), the Intelligence Advanced Research Projects Activity (IARPA) under the Army Research Office (ARO), the European Commission under the Integrated Project Qubit Applications (QAP) and Quantum Interfaces, Sensors, and Communication based on Entanglement (Q-ESSENCE) and the IST directorate, the ERC Senior Grant (QIT4QAD) and the Marie-Curie research training network EMALI.
Author information
Authors and Affiliations
Contributions
S.B. and G.C. designed and performed experiments, analysed data and wrote the manuscript. A.Z. supervised the project and edited the manuscript. P.W. designed experiments, analysed data, wrote the manuscript and supervised the project.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing financial interests.
Supplementary information
Rights and permissions
About this article
Cite this article
Barz, S., Cronenberg, G., Zeilinger, A. et al. Heralded generation of entangled photon pairs. Nature Photon 4, 553–556 (2010). https://doi.org/10.1038/nphoton.2010.156
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/nphoton.2010.156
This article is cited by
-
Controlling two-photon emission from superluminal and accelerating index perturbations
Nature Physics (2022)
-
Quantum-dot-based deterministic photon–emitter interfaces for scalable photonic quantum technology
Nature Nanotechnology (2021)
-
Creating heralded hyper-entangled photons using Rydberg atoms
Light: Science & Applications (2021)
-
Entanglement and teleportation between polarization and wave-like encodings of an optical qubit
Nature Communications (2018)
-
Experimental optical phase measurement approaching the exact Heisenberg limit
Nature Communications (2018)