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Fundamental limits of repeaterless quantum communications

Stefano Pirandola, Riccardo Laurenza, Carlo Ottaviani and 1 more

Nature Communications · 2017 · CC BY

doi:10.1038/ncomms15043

Abstract

Quantum communications promises reliable transmission of quantum information, efficient distribution of entanglement and generation of completely secure keys. For all these tasks, we need to determine the optimal point-to-point rates that are achievable by two remote parties at the ends of a quantum channel, without restrictions on their local operations and classical communication, which can be unlimited and two-way. These two-way assisted capacities represent the ultimate rates that are reachable without quantum repeaters. Here, by constructing an upper bound based on the relative entropy of entanglement and devising a dimension-independent technique dubbed ‘teleportation stretching’, we establish these capacities for many fundamental channels, namely bosonic lossy channels, quantum-limited amplifiers, dephasing and erasure channels in arbitrary dimension. In particular, we exactly determine the fundamental rate-loss tradeoff affecting any protocol of quantum key distribution. Our findings set the limits of point-to-point quantum communications and provide precise and general benchmarks for quantum repeaters.

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References 69

  1. 1.

    Nielsen M. A. & Chuang I. L. Quantum Computation and Quantum Information Cambridge Univ. Press (2000 ).

    Not in our library

  2. 2.

    Weedbrook C.. Gaussian quantum information. Rev. Mod. Phys. 84, 621–669 (2012 ).

    Not in our library

  3. 3.

    Holevo A. in Quantum Systems, Channels, Information: A Mathematical Introduction De Gruyter (2012 ).

    Not in our library

  4. 4.

    Bennett C. H. & Brassard G. in Proceedings of IEEE International Conference on Computers, Systems, and Signal Processing, 175–179 (Bangalore, India, 1984).

    Not in our library

  5. 5.

    Gisin N., Ribordy G., Tittel W. & Zbinden H. Quantum cryptography. Rev. Mod. Phys. 74, 145–196 (2002 ).

    Not in our library

  6. 6.

    Scarani V.. The security of practical quantum key distribution. Rev. Mod. Phys. 81, 1301–1350 (2009 ).

    Not in our library

  7. 7.

    Kimble H. J. The quantum internet. Nature 453, 1023–1030 (2008 ).

    Not in our library10.1038/nature07127

  8. 8.

    Pirandola S. & Braunstein S. L. Unite to build a quantum internet. Nature 532, 169–171 (2016 ).

    Not in our library10.1038/532169a

  9. 9.

    Pirandola S.. Advances in quantum teleportation. Nat. Photon. 9, 641–652 (2015 ).

    Not in our library

  10. 10.

    Andersen U. L., Neergaard-Nielsen J. S., van Loock P. & Furusawa A. Hybrid discrete- and continuous-variable quantum information. Nat. Phys. 11, 713–719 (2015 ).

    Not in our library

  11. 11.

    Briegel H.-J., Dür W., Cirac J. I. & Zoller P. Quantum repeaters: the role of imperfect local operations in quantum communication. Phys. Rev. Lett. 81, 5932–5935 (1998 ).

    Not in our library

  12. 12.

    Bennett C. H., DiVincenzo D. P. & Smolin J. A. Capacities of quantum erasure channels. Phys. Rev. Lett. 78, 3217–3220 (1997 ).

    Not in our library

  13. 13.

    Grosshans F.. Quantum key distribution using gaussian-modulated coherent states. Nature 421, 238–241 (2003 ).

    Not in our library10.1038/nature01289

  14. 14.

    Garca-Patrón R., Pirandola S., Lloyd S. & Shapiro J. H. Reverse coherent information. Phys. Rev. Lett. 102, 210501 (2009 ).

    Not in our library10.1103/physrevlett.102.210501

  15. 15.

    Devetak I. The private classical capacity and quantum capacity of a quantum channel. IEEE Trans. Info. Theory 51, 44–55 (2005 ).

    Not in our library

  16. 16.

    Devetak I. & Winter A. Distillation of secret key and entanglement from quantum states. Proc. R. Soc. A 461, 207–235 (2005 ).

    Not in our library

  17. 17.

    Pirandola S., Garca-Patrón R., Braunstein S. L. & Lloyd S. Direct and reverse secret-key capacities of a quantum channel. Phys. Rev. Lett. 102, 050503 (2009 ).

    Not in our library10.1103/physrevlett.102.050503

  18. 18.

    Takeoka M., Guha S. & Wilde M. M. Fundamental rate-loss tradeoff for optical quantum key distribution. Nat. Commun. 5, 5235 (2014 ).

    Not in our library10.1038/ncomms6235

  19. 19.

    Christandl M. The Structure of Bipartite Quantum States: Insights from Group Theory and Cryptography (PhD thesis, University of Cambridge, 2006).

    Not in our library

  20. 20.

    Pirandola S.. High-rate measurement-device-independent quantum cryptography. Nat. Photon. 9, 397–402 (2015 ).

    Not in our library

  21. 21.

    Vedral V., Plenio M. B., Rippin M. A. & Knight P. L. Quantifying Entanglement. Phys. Rev. Lett. 78, 2275–2279 (1997 ).

    Not in our library

  22. 22.

    Vedral V. & Plenio M. B. Entanglement measures and purification procedures. Phys. Rev. A 57, 1619–1633 (1998 ).

    Not in our library

  23. 23.

    Vedral V. The role of relative entropy in quantum information theory. Rev. Mod. Phys. 74, 197–234 (2002 ).

    Not in our library

  24. 24.

    Bennett C. H.. Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels. Phys. Rev. Lett. 70, 1895–1899 (1993 ).

    Not in our library10.1103/physrevlett.70.1895

  25. 25.

    Braunstein S. L. & Kimble H. J. Teleportation of continuous quantum variables. Phys. Rev. Lett. 80, 869–872 (1998 ).

    Not in our library

  26. 26.

    Braunstein S. L., D'Ariano G. M., Milburn G. J. & Sacchi M. F. Universal teleportation with a twist. Phys. Rev. Lett. 84, 3486–3489 (2000 ).

    Not in our library10.1103/physrevlett.84.3486

  27. 27.

    Horodecki K., Horodecki M., Horodecki P. & Oppenheim J. Secure key from bound entanglement. Phys. Rev. Lett. 94, 160502 (2005 ).

    Not in our library10.1103/physrevlett.94.160502

  28. 28.

    Schumacher B. & Nielsen M. A. Quantum data processing and error correction. Phys. Rev. A 54, 2629–2635 (1996 ).

    Not in our library10.1103/physreva.54.2629

  29. 29.

    Lloyd S. Capacity of the noisy quantum channel. Phys. Rev. A 55, 1613–1622 (1997 ).

    Not in our library

  30. 30.

    Christiandl M., Schuch N. & Winter A. Entanglement of the antisymmetric state. Commun. Math. Phys. 311, 397–422 (2012 ).

    Not in our library

  31. 31.

    Bennett C. H., DiVincenzo D. P., Smolin J. A. & Wootters W. K. Mixed-state entanglement and quantum error correction. Phys. Rev. A 54, 3824–3851 (1996 ).

    Not in our library10.1103/physreva.54.3824

  32. 32.

    Horodecki M., Horodecki P. & Horodecki R. General teleportation channel, singlet fraction, and quasidistillation. Phys. Rev. A 99, 1888–1898 (1999 ).

    Not in our library

  33. 33.

    Bowen G. & Bose S. Teleportation as a depolarizing quantum channel, relative entropy and classical capacity. Phys. Rev. Lett. 87, 267901 (2001 ).

    Not in our library10.1103/physrevlett.87.267901

  34. 34.

    Albeverio S., Fei S.-M. & Yang W.-L. Optimal teleportation based on Bell measurements. Phys. Rev. A 66, 012301 (2002 ).

    Not in our library

  35. 35.

    Müller-Hermes A. Transposition in Quantum Information Theory (MSc Thesis, Technische Universität München, 2012).

    Not in our library

  36. 36.

    Leung D. & Matthews W. On the power of ppt-preserving and nonsignalling codes. IEEE Trans. Inf. Theory 61, 4486–4499 (2015 ).

    Not in our library

  37. 37.

    Werner R. F. All teleportation and dense coding schemes. J. Phys. A 34, 7081–7094 (2001 ).

    Not in our library

  38. 38.

    Niset J., Fiurasek J. & Cerf N. J. No-go theorem for Gaussian quantum error correction. Phys. Rev. Lett. 102, 120501 (2009 ).

    Not in our library10.1103/physrevlett.102.120501

  39. 39.

    Ji Z., Wang G., Duan R., Feng Y. & Ying M. Parameter estimation of quantum channels. IEEE Trans. Inform. Theory 54, 5172–5185 (2008 ).

    Not in our library

  40. 40.

    Nielsen M. A. & Chuang I. L. Programmable quantum gate arrays. Phys. Rev. Lett. 79, 321–324 (1997 ).

    Not in our library

  41. 41.

    Modi K.. The classical-quantum boundary for correlations: discord and related measures. Rev. Mod. Phys. 84, 1655–1707 (2012 ).

    Not in our library

  42. 42.

    Pirandola S. Quantum discord as a resource for quantum cryptography. Sci. Rep. 4, 6956 (2014 ).

    Not in our library10.1038/srep06956

  43. 43.

    Pirandola S., Spedalieri G., Braunstein S. L., Cerf N. J. & Lloyd S. Optimality of Gaussian discord. Phys. Rev. Lett. 113, 140405 (2014 ).

    Not in our library10.1103/physrevlett.113.140405

  44. 44.

    Hosseinidehaj N. & Malaney R. Gaussian entanglement distribution via satellite. Phys. Rev. A 91, 022304 (2015 ).

    Not in our library

  45. 45.

    Vallone G.. Experimental satellite quantum communications. Phys. Rev. Lett. 115, 040502 (2015 ).

    Not in our library10.1103/physrevlett.115.040502

  46. 46.

    Dequal D.. Experimental single-photon exchange along a space link of 7,000 km. Phys. Rev. A 93, 010301 (R) (2016 ).

    Not in our library

  47. 47.

    Usenko V. C. & Filip R. Feasibility of continuous-variable quantum key distribution with noisy coherent states. Phys. Rev. A 81, 022318 (2010 ).

    Not in our library

  48. 48.

    Weedbrook C.. Quantum cryptography approaching the classical limit. Phys. Rev. Lett. 105, 110501 (2010 ).

    Not in our library10.1103/physrevlett.105.110501

  49. 49.

    Weedbrook C.. Continuous-variable quantum key distribution using thermal states. Phys. Rev. A 86, 022318 (2012 ).

    Not in our library

  50. 50.

    Weedbrook C., Ottaviani C. & Pirandola S. Two-way quantum cryptography at different wavelengths. Phys. Rev. A 89, 012309 (2014 ).

    Not in our library

  51. 51.

    Holevo A. S. & Werner R. F. Evaluating capacities of bosonic Gaussian channels. Phys. Rev. A 63, 032312 (2001 ).

    Not in our library

  52. 52.

    Wolf M. M., Pérez-Garca D. & Giedke G. Quantum capacities of bosonic channels. Phys. Rev. Lett. 98, 130501 (2007 ).

    Not in our library10.1103/physrevlett.98.130501

  53. 53.

    Devetak I. & Shor P. W. The capacity of a quantum channel for simultaneous transmission of classical and quantum information. Commun. Math. Phys. 256, 287–303 (2005 ).

    Not in our library

  54. 54.

    Goodenough K., Elkouss D. & Wehner S. Assessing the performance of quantum repeaters for all phase-insensitive Gaussian bosonic channels. Preprint at https://arxiv.org/abs/1511.08710v1 (2015 ).

    Not in our library

  55. 55.

    Bose S. Quantum communication through an Unmodulated Spin Chain. Phys. Rev. Lett. 20, 207901 (2003 ).

    Not in our library10.1103/physrevlett.91.207901

  56. 56.

    Bose S., Bayat A., Sodano P., Banchi L. & Verrucchi P. in Quantum State Transfer and Network Engineering 1–37Springer (2014 ).

    Not in our library

  57. 57.

    Pirandola S. Capacities of repeater-assisted quantum communications. Preprint at https://arxiv.org/abs/1601.00966 (2016 ).

    Not in our library

  58. 58.

    Pirandola S. & Lupo C. Ultimate precision of adaptive noise estimation. Phys. Rev. Lett. 118, 100502 (2017 ).

    Not in our library10.1103/physrevlett.118.100502

  59. 59.

    Dutta A. B., Mukunda N. & Simon R. The real symplectic groups in quantum mechanics and optics. Pramana 45, 471–497 (1995 ).

    Not in our library

  60. 60.

    Banchi L., Braunstein S. L. & Pirandola S. Quantum fidelity for arbitrary Gaussian states. Phys. Rev. Lett. 115, 260501 (2015 ).

    Not in our library10.1103/physrevlett.115.260501

  61. 61.

    Chen X. Y. Gaussian relative entropy of entanglement. Phys. Rev. A 71, 062320 (2005 ).

    Not in our library

  62. 62.

    Scheel S. & Welsch D.-G. Entanglement generation and degradation by passive optical devices. Phys. Rev. A 64, 063811 (2001 ).

    Not in our library

  63. 63.

    Weedbrook C.. Quantum cryptography without switching. Phys. Rev. Lett. 93, 170504 (2004 ).

    Not in our library10.1103/physrevlett.93.170504

  64. 64.

    Ottaviani C., Spedalieri G., Braunstein S. L. & Pirandola S. Continuous-variable quantum cryptography with an untrusted relay: detailed security analysis of the symmetric configuration. Phys. Rev. A 91, 022320 (2015 ).

    Not in our library

  65. 65.

    Spedalieri G.. in Proceedings of SPIE Security+Defence 2015 Conference on Quantum Information Science and Technology 9648-47 (Toulouse, France, 2015).

    Not in our library

  66. 66.

    Pirandola S., Mancini S., Lloyd S. & Braunstein S. L. Continuous-variable quantum cryptography using two-way quantum communication. Nat. Phys. 4, 726–730 (2008 ).

    Not in our library

  67. 67.

    Ottaviani C. & Pirandola S. General immunity and superadditivity of two-way Gaussian quantum cryptography. Sci. Rep. 6, 22225 (2016 ).

    Not in our library10.1038/srep22225

  68. 68.

    Braunstein S. L. & Pirandola S. Side-channel-free quantum key distribution. Phys. Rev. Lett. 108, 130502 (2012 ).

    Not in our library10.1103/physrevlett.108.130502

  69. 69.

    Lo H.-K., Curty M. & Qi B. Measurement-Device-Independent Quantum Key Distribution. Phys. Rev. Lett. 108, 130503 (2012 ).

    Not in our library10.1103/physrevlett.108.130503

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