Entanglement swapping with independent sources over an optical-fiber network

Teleportation of an entangled state, known as entanglement swapping, plays an essential role in quantum communication and network.Here we report a field-test entanglement swapping experiment with two independent telecommunication band entangled photon-pair sources over the optical fibre network of Hefei city. The two sources are located at two nodes 12 km apart and the Bell-state measurement is performed in a third location which is connected to the two source nodes with 14.7 km and 10.6 km optical fibres. An average visibility of 79.9+/-4.8% is observed in our experiment, which is high enough to infer a violation of Bell inequality. With the entanglement swapping setup, we demonstrate a source independent quantum key distribution, which is also immune to any attack against detection in the measurement site.

[1]  H. Lo,et al.  Decoy-state quantum key distribution with two-way classical postprocessing , 2006, quant-ph/0604094.

[2]  Charles H. Bennett,et al.  Quantum cryptography without Bell's theorem. , 1992, Physical review letters.

[3]  Umesh Vazirani,et al.  Fully device-independent quantum key distribution. , 2012, 1210.1810.

[4]  Robert B. Ash,et al.  Information Theory , 2020, The SAGE International Encyclopedia of Mass Media and Society.

[5]  Ilgaitis Prūsis,et al.  Nature of Photon , 2019 .

[6]  Wolfgang Tittel,et al.  Quantum storage of entangled telecom-wavelength photons in an erbium-doped optical fibre , 2014, Nature Photonics.

[7]  R. Serfling Probability Inequalities for the Sum in Sampling without Replacement , 1974 .

[8]  Wolfgang Dür,et al.  Quantum Repeaters: The Role of Imperfect Local Operations in Quantum Communication , 1998 .

[9]  Masahide Sasaki,et al.  Highly efficient entanglement swapping and teleportation at telecom wavelength , 2014, Scientific Reports.

[10]  Chun-Mei Zhang,et al.  Improved statistical fluctuation analysis for measurement-device-independent quantum key distribution , 2012 .

[11]  Robert Prevedel,et al.  High-fidelity entanglement swapping with fully independent sources , 2008, 0809.3991.

[12]  Shor,et al.  Simple proof of security of the BB84 quantum key distribution protocol , 2000, Physical review letters.

[13]  Charles H. Bennett,et al.  Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels. , 1993, Physical review letters.

[14]  M. Curty,et al.  Measurement-device-independent quantum key distribution. , 2011, Physical review letters.

[15]  Zhu Cao,et al.  Performance of device-independent quantum key distribution , 2016 .

[16]  W Tittel,et al.  Distribution of time-bin entangled qubits over 50 km of optical fiber. , 2004, Physical review letters.

[17]  Asher Peres Delayed choice for entanglement swapping , 2000 .

[18]  Christoph Simon,et al.  Entangling independent photons by time measurement , 2007, 0704.0758.

[19]  Marek Zukowski,et al.  Experimental interference of independent photons. , 2006, Physical review letters.

[20]  J. Cirac,et al.  Long-distance quantum communication with atomic ensembles and linear optics , 2001, Nature.

[21]  H. Lo,et al.  Quantum key distribution with entangled photon sources , 2007, quant-ph/0703122.

[22]  Ekert,et al.  "Event-ready-detectors" Bell experiment via entanglement swapping. , 1993, Physical review letters.

[23]  A. Zeilinger,et al.  Teleportation of entanglement over 143 km , 2014, Proceedings of the National Academy of Sciences.

[24]  H. Lo,et al.  Quantum key distribution with triggering parametric down-conversion sources , 2008, 0803.2543.

[25]  Miss A.O. Penney (b) , 1974, The New Yale Book of Quotations.

[26]  Experimental synchronization of independent entangled photon sources. , 2005, Physical review letters.

[27]  N. Gisin,et al.  Long-distance entanglement swapping with photons from separated sources , 2004, quant-ph/0409093.

[28]  A. Shimony,et al.  Proposed Experiment to Test Local Hidden Variable Theories. , 1969 .

[29]  J. Bell On the Einstein-Podolsky-Rosen paradox , 1964 .

[30]  John Preskill,et al.  Secure quantum key distribution with an uncharacterized source. , 2003, Physical review letters.

[31]  Normand J. Beaudry,et al.  Squashing models for optical measurements in quantum communication. , 2008, Physical review letters.

[32]  Hoi-Kwong Lo,et al.  Proof of security of quantum key distribution with two-way classical communications , 2001, IEEE Trans. Inf. Theory.

[33]  Wei Zhang,et al.  Quantum teleportation with independent sources and prior entanglement distribution over a network , 2016, Nature Photonics.

[34]  Franson,et al.  Bell inequality for position and time. , 1989, Physical review letters.

[35]  H. Weinfurter,et al.  Experimental Entanglement Swapping: Entangling Photons That Never Interacted , 1998 .

[36]  Thierry Paul,et al.  Quantum computation and quantum information , 2007, Mathematical Structures in Computer Science.

[37]  Wei Cui,et al.  Finite-key analysis for measurement-device-independent quantum key distribution , 2013, Nature Communications.

[38]  Jian-Wei Pan,et al.  Source attack of decoy-state quantum key distribution using phase information , 2013, 1304.2541.

[39]  L. Goddard Information Theory , 1962, Nature.

[40]  Mohamed Bourennane,et al.  Hacking the Bell test using classical light in energy-time entanglement–based quantum key distribution , 2015, Science Advances.

[41]  S. Wehner,et al.  Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres , 2015, Nature.