High-fidelity entanglement swapping and generation of three-qubit GHZ state using asynchronous telecom photon pair sources

We experimentally demonstrate a high-fidelity entanglement swapping and a generation of the Greenberger-Horne-Zeilinger (GHZ) state using polarization-entangled photon pairs at telecommunication wavelength produced by spontaneous parametric down conversion with continuous-wave pump light. While spatially separated sources asynchronously emit photon pairs, the time-resolved photon detection guarantees the temporal indistinguishability of photons without active timing synchronizations of pump lasers and/or adjustment of optical paths. In the experiment, photons are sufficiently narrowed by fiber-based Bragg gratings with the central wavelengths of 1541 nm & 1580 nm, and detected by superconducting nanowire single-photon detectors with low timing jitters. The observed fidelities of the final states for entanglement swapping and the generated three-qubit state were 0.84 ± 0.04 and 0.70 ± 0.05, respectively.

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

[2]  Zach DeVito,et al.  Opt , 2017 .

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

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

[5]  B. Sanders,et al.  Long-distance practical quantum key distribution by entanglement swapping. , 2010, Optics express.

[6]  Akio Yoshizawa,et al.  Wavelength-multiplexed entanglement distribution , 2010 .

[7]  H. Weinfurter,et al.  Observation of three-photon Greenberger-Horne-Zeilinger entanglement , 1998, quant-ph/9810035.

[8]  E. Knill,et al.  Diluted maximum-likelihood algorithm for quantum tomography , 2006, quant-ph/0611244.

[9]  J. D. Franson,et al.  Probabilistic quantum logic operations using polarizing beam splitters , 2001, quant-ph/0107091.

[10]  Cheng-Zhi Peng,et al.  Experimental quantum teleportation and multiphoton entanglement via interfering narrowband photon sources , 2009, 0901.0351.

[11]  N. Gisin,et al.  Quantum relays for long distance quantum cryptography , 2003, quant-ph/0311101.

[12]  M. Koashi,et al.  High visibility Hong-Ou-Mandel interference via a time-resolved coincidence measurement. , 2015, Optics express.

[13]  J. D. Franson,et al.  Quantum relays and noise suppression using linear optics , 2002 .

[14]  Rupert Ursin,et al.  Quantum teleportation and entanglement swapping with linear optics logic gates , 2008, 0809.3689.

[15]  C. Monroe,et al.  Large-scale modular quantum-computer architecture with atomic memory and photonic interconnects , 2012, 1208.0391.

[16]  W. Wootters.  Entanglement of Formation of an Arbitrary State of Two Qubits , 1997, quant-ph/9709029.

[17]  Gregor Weihs,et al.  Experimental nonlocality proof of quantum teleportation and entanglement swapping. , 2002, Physical review letters.

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

[19]  E. Knill,et al.  A scheme for efficient quantum computation with linear optics , 2001, Nature.

[20]  Nicolas Gisin,et al.  Quantum repeaters based on atomic ensembles and linear optics , 2009, 0906.2699.

[21]  Djeylan Aktas,et al.  Entanglement distribution over 150 km in wavelength division multiplexed channels for quantum cryptography , 2016, 1601.02402.

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

[23]  Stefano Pirandola,et al.  High-rate measurement-device-independent quantum cryptography , 2013, Nature Photonics.

[24]  Christian Kurtsiefer,et al.  Experimental detection of multipartite entanglement using witness operators. , 2004, Physical review letters.

[25]  Charles K. Kao.  Optical fiber technology, II , 1981 .

[26]  M. Lewenstein,et al.  Classification of mixed three-qubit states. , 2001, Physical review letters.

[27]  L. A. Ngah,et al.  Toward Continuous-Wave Regime Teleportation for Light Matter Quantum Relay Stations , 2014, IEEE Journal of Selected Topics in Quantum Electronics.

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

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

[30]  H. Bechmann-Pasquinucci,et al.  Quantum cryptography , 2001, quant-ph/0101098.

[31]  Charles H. Bennett,et al.  Mixed-state entanglement and quantum error correction. , 1996, Physical review. A, Atomic, molecular, and optical physics.

[32]  Jian-Wei Pan,et al.  Experimental quantum secret sharing and third-man quantum cryptography. , 2005, Physical review letters.

[33]  Nicolas Gisin,et al.  High coherence photon pair source for quantum communication , 2007, 0710.1143.