Abstract

We report the first gigahertz clocked decoy-protocol quantum key distribution (QKD). Record key rates have been achieved thanks to the use of self-differencing InGaAs avalanche photodiodes designed specifically for high speed single photon detection. The system is characterized with a secure key rate of 1.02 Mbit/s for a fiber distance of 20 km and 10.1 kbit/s for 100 km. As the present advance relies upon compact non-cryogenic detectors, it opens the door towards practical and low cost QKD systems to secure broadband communication in future.

© 2008 Optical Society of America

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  8. H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki and Y. Yamamoto, "Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors," Nat. Photonics 1, 343-348 (2007).
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  9. K. J. Gordon, V. Fernandez, G. S. Buller, I. Rech, S. D. Cova and P. D. Townsend, "Quantum key distribution system clocked at 2 GHz," Opt. Express 13, 3015-3020 (2005).
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    [CrossRef]
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    [CrossRef]
  29. Our time-tagging electronics record each photon with a 32-bit number to represent its arrival time. Due to restriction in the data bandwidth at around 160 Mbit/s per channel, for transferring photon information into computer memory, each channel can cope with only 5 million photons per second at most.
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    [CrossRef]
  31. A. Tanaka, M. Fujiwara, S.W. Nam, Y. Nambu, S. Takahashi, W. Maeda, K. Yoshino, S. Miki, B. Baek, Z. Wang, A. Tajima, M. Sasaki and A. Tomita, "Ultra fast quantum key distribution over a 97 km installed telecom fiber with wavelength division multiplexing clock synchronization," Opt. Express 16, 11354-11360 (2008).
    [CrossRef] [PubMed]

2008

Z. L. Yuan, A. R. Dixon, J. F. Dynes, A. W. Sharpe and A. J. Shields, "Gigahertz quantum key distribution with InGaAs avalanche photodiodes," Appl. Phys. Lett. 92, 201104 (2008).
[CrossRef]

J. F. Dynes, Z. L. Yuan, A. W. Sharpe and A. J. Shields, "A high speed, post-processing free, quantum random number generator," Appl. Phys. Lett. 93, 031109 (2008).
[CrossRef]

A. Tanaka, M. Fujiwara, S.W. Nam, Y. Nambu, S. Takahashi, W. Maeda, K. Yoshino, S. Miki, B. Baek, Z. Wang, A. Tajima, M. Sasaki and A. Tomita, "Ultra fast quantum key distribution over a 97 km installed telecom fiber with wavelength division multiplexing clock synchronization," Opt. Express 16, 11354-11360 (2008).
[CrossRef] [PubMed]

2007

Z. L. Yuan, A. W. Sharpe and A. J. Shields, "Unconditionally secure quantum key distribution using decoy pulses," Appl. Phys. Lett. 90, 011118 (2007).
[CrossRef]

D. Rosenberg, J. W. Harrington, P. R. Rice, P. A. Hiskett, C. G. Peterson, R. J. Hughes, A. E. Lita, S. W. Nam, and J. E. Nordholt, "Long-distance decoy-state quantum key distribution in optical fiber," Phys. Rev. Lett. 98, 010503 (2007).
[CrossRef] [PubMed]

C. Z. Peng, J. Zhang, D. Yang, W.-B. Gao, H.-X. Ma, H. Yin, H. P. Zeng, T. Yang, X.-B. Wang and J. W. Pan, "Experimental long-distance decoy-state quantum key distribution based on polarisation encoding," Phys. Rev. Lett. 98, 010505 (2007).
[CrossRef] [PubMed]

J. F. Dynes, Z. L. Yuan, A. W. Sharpe and A. J. Shields, "Practical quantum key distribution over 60 hours at an optical fiber distance of 20 km using weak and vacuum decoy pulses for enhanced security," Opt. Express 15, 8465 - 8471 (2007).
[CrossRef] [PubMed]

Z. L. Yuan, B. E. Kardynal, A. W. Sharpe and A. J. Shields, "High speed single photon detection in the near infrared," Appl. Phys. Lett. 91, 041114 (2007).
[CrossRef]

H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki and Y. Yamamoto, "Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors," Nat. Photonics 1, 343-348 (2007).
[CrossRef]

2006

A. Mink, X. Tang, L. J. Ma, T. Nakassis, B. Hershman, J. C. Bienfang, D. Su, R. Boisvert, C. W. Clark and C. J. Williams, "High speed quantum key distribution system supports one-time pad encryption of real-time video," Proc. SPIE 6244, 62440M (2006).
[CrossRef]

2005

Z. L. Yuan and A. J. Shields, "Continuous operation of a one-way quantum key distribution system over installed telecom fibre," Opt. Express 13, 660-665 (2005).
[CrossRef] [PubMed]

K. J. Gordon, V. Fernandez, G. S. Buller, I. Rech, S. D. Cova and P. D. Townsend, "Quantum key distribution system clocked at 2 GHz," Opt. Express 13, 3015-3020 (2005).
[CrossRef] [PubMed]

H. K. Lo, X. Ma and K. Chen, "Decoy state quantum key distribution," Phys. Rev. Lett. 94, 230504 (2005).
[CrossRef] [PubMed]

X. Ma, B. Qi, Y. Zhao and H. K. Lo, "Practical decoy state for quantum key distribution," Phys. Rev. A 72, 012326 (2005).
[CrossRef]

X. B. Wang, "Beating the photon-number-splitting attack in practical quantum cryptography," Phys. Rev. Lett. 94, 230503 (2005).
[CrossRef] [PubMed]

X. B. Wang, "Decoy-state protocol for quantum cryptography with four different intensities of coherent light," Phys. Rev. A 72, 012322 (2005).
[CrossRef]

D. Stucki, N. Brunner, N. Gisin, V. Scarani and H. Zbinden, "Fast and simple one-way quantum key distribution," Appl. Phys. Lett. 87, 194108 (2005).
[CrossRef]

2004

D. Gottesman, H. K. Lo, N. Lütkenhaus and J. Preskill, "Security of quantum key distribution with imperfect devices," Quantum. Inf. Comput. 4, 325-360 (2004).

2003

W. Y. Hwang, "Quantum key distribution with high loss: towards global secure communication," Phys. Rev. Lett. 91, 057901 (2003).
[CrossRef] [PubMed]

2002

K. Inoue, E. Waks and Y. Yamamoto, "Differential phase shift quantum key distribution," Phys. Rev. Lett. 89, 037902 (2002).
[CrossRef] [PubMed]

N. Gisin, G. Ribordy,W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145-195 (2002).
[CrossRef]

C. Gobby, Z. L. Yuan and A. J. Shields, "Quantum key distribution over 122 km telecom fiber," Appl. Phys. Lett. 84, 3762-3764 (2002).
[CrossRef]

2000

G. Brassard, N. Lütkenhaus, T. Mor and B. C. Sanders, "Limitations on practical quantum cryptography," Phys. Rev. Lett. 85, 1330-1333 (2000).
[CrossRef] [PubMed]

1999

M. Dusek, O. Haderka and M. Hendrych,"Generalized beam-splitting attack in quantum cryptography with dim coherent states," Opt. Commun. 169, 103-108 (1999).
[CrossRef]

1993

P. Townsend, J. G. Rarity and P. R. Tapster, "Single-photon interference in 10 km long optical fiber interferometer," Electron. Lett. 29, 634-639 (1993).
[CrossRef]

1992

C. H. Bennett, F. Bessette, G. Brassard, L. Salvail, and J. Smolin, "Experimental quantum cryptography," J. Cryptol. 5, 3-28 (1992).
[CrossRef]

Baek, B.

Bennett, C. H.

C. H. Bennett, F. Bessette, G. Brassard, L. Salvail, and J. Smolin, "Experimental quantum cryptography," J. Cryptol. 5, 3-28 (1992).
[CrossRef]

Bessette, F.

C. H. Bennett, F. Bessette, G. Brassard, L. Salvail, and J. Smolin, "Experimental quantum cryptography," J. Cryptol. 5, 3-28 (1992).
[CrossRef]

Bienfang, J. C.

A. Mink, X. Tang, L. J. Ma, T. Nakassis, B. Hershman, J. C. Bienfang, D. Su, R. Boisvert, C. W. Clark and C. J. Williams, "High speed quantum key distribution system supports one-time pad encryption of real-time video," Proc. SPIE 6244, 62440M (2006).
[CrossRef]

Boisvert, R.

A. Mink, X. Tang, L. J. Ma, T. Nakassis, B. Hershman, J. C. Bienfang, D. Su, R. Boisvert, C. W. Clark and C. J. Williams, "High speed quantum key distribution system supports one-time pad encryption of real-time video," Proc. SPIE 6244, 62440M (2006).
[CrossRef]

Brassard, G.

G. Brassard, N. Lütkenhaus, T. Mor and B. C. Sanders, "Limitations on practical quantum cryptography," Phys. Rev. Lett. 85, 1330-1333 (2000).
[CrossRef] [PubMed]

C. H. Bennett, F. Bessette, G. Brassard, L. Salvail, and J. Smolin, "Experimental quantum cryptography," J. Cryptol. 5, 3-28 (1992).
[CrossRef]

Brunner, N.

D. Stucki, N. Brunner, N. Gisin, V. Scarani and H. Zbinden, "Fast and simple one-way quantum key distribution," Appl. Phys. Lett. 87, 194108 (2005).
[CrossRef]

Buller, G. S.

Chen, K.

H. K. Lo, X. Ma and K. Chen, "Decoy state quantum key distribution," Phys. Rev. Lett. 94, 230504 (2005).
[CrossRef] [PubMed]

Clark, C. W.

A. Mink, X. Tang, L. J. Ma, T. Nakassis, B. Hershman, J. C. Bienfang, D. Su, R. Boisvert, C. W. Clark and C. J. Williams, "High speed quantum key distribution system supports one-time pad encryption of real-time video," Proc. SPIE 6244, 62440M (2006).
[CrossRef]

Cova, S. D.

Dixon, A. R.

Z. L. Yuan, A. R. Dixon, J. F. Dynes, A. W. Sharpe and A. J. Shields, "Gigahertz quantum key distribution with InGaAs avalanche photodiodes," Appl. Phys. Lett. 92, 201104 (2008).
[CrossRef]

Dusek, M.

M. Dusek, O. Haderka and M. Hendrych,"Generalized beam-splitting attack in quantum cryptography with dim coherent states," Opt. Commun. 169, 103-108 (1999).
[CrossRef]

Dynes, J. F.

Z. L. Yuan, A. R. Dixon, J. F. Dynes, A. W. Sharpe and A. J. Shields, "Gigahertz quantum key distribution with InGaAs avalanche photodiodes," Appl. Phys. Lett. 92, 201104 (2008).
[CrossRef]

J. F. Dynes, Z. L. Yuan, A. W. Sharpe and A. J. Shields, "A high speed, post-processing free, quantum random number generator," Appl. Phys. Lett. 93, 031109 (2008).
[CrossRef]

J. F. Dynes, Z. L. Yuan, A. W. Sharpe and A. J. Shields, "Practical quantum key distribution over 60 hours at an optical fiber distance of 20 km using weak and vacuum decoy pulses for enhanced security," Opt. Express 15, 8465 - 8471 (2007).
[CrossRef] [PubMed]

Fernandez, V.

Fujiwara, M.

Gao, W.-B.

C. Z. Peng, J. Zhang, D. Yang, W.-B. Gao, H.-X. Ma, H. Yin, H. P. Zeng, T. Yang, X.-B. Wang and J. W. Pan, "Experimental long-distance decoy-state quantum key distribution based on polarisation encoding," Phys. Rev. Lett. 98, 010505 (2007).
[CrossRef] [PubMed]

Gisin, N.

D. Stucki, N. Brunner, N. Gisin, V. Scarani and H. Zbinden, "Fast and simple one-way quantum key distribution," Appl. Phys. Lett. 87, 194108 (2005).
[CrossRef]

N. Gisin, G. Ribordy,W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145-195 (2002).
[CrossRef]

Gobby, C.

C. Gobby, Z. L. Yuan and A. J. Shields, "Quantum key distribution over 122 km telecom fiber," Appl. Phys. Lett. 84, 3762-3764 (2002).
[CrossRef]

Gordon, K. J.

Gottesman, D.

D. Gottesman, H. K. Lo, N. Lütkenhaus and J. Preskill, "Security of quantum key distribution with imperfect devices," Quantum. Inf. Comput. 4, 325-360 (2004).

Haderka, O.

M. Dusek, O. Haderka and M. Hendrych,"Generalized beam-splitting attack in quantum cryptography with dim coherent states," Opt. Commun. 169, 103-108 (1999).
[CrossRef]

Hadfield, R. H.

H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki and Y. Yamamoto, "Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors," Nat. Photonics 1, 343-348 (2007).
[CrossRef]

Harrington, J. W.

D. Rosenberg, J. W. Harrington, P. R. Rice, P. A. Hiskett, C. G. Peterson, R. J. Hughes, A. E. Lita, S. W. Nam, and J. E. Nordholt, "Long-distance decoy-state quantum key distribution in optical fiber," Phys. Rev. Lett. 98, 010503 (2007).
[CrossRef] [PubMed]

Hendrych, M.

M. Dusek, O. Haderka and M. Hendrych,"Generalized beam-splitting attack in quantum cryptography with dim coherent states," Opt. Commun. 169, 103-108 (1999).
[CrossRef]

Hershman, B.

A. Mink, X. Tang, L. J. Ma, T. Nakassis, B. Hershman, J. C. Bienfang, D. Su, R. Boisvert, C. W. Clark and C. J. Williams, "High speed quantum key distribution system supports one-time pad encryption of real-time video," Proc. SPIE 6244, 62440M (2006).
[CrossRef]

Hiskett, P. A.

D. Rosenberg, J. W. Harrington, P. R. Rice, P. A. Hiskett, C. G. Peterson, R. J. Hughes, A. E. Lita, S. W. Nam, and J. E. Nordholt, "Long-distance decoy-state quantum key distribution in optical fiber," Phys. Rev. Lett. 98, 010503 (2007).
[CrossRef] [PubMed]

Honjo, T.

H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki and Y. Yamamoto, "Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors," Nat. Photonics 1, 343-348 (2007).
[CrossRef]

Hughes, R. J.

D. Rosenberg, J. W. Harrington, P. R. Rice, P. A. Hiskett, C. G. Peterson, R. J. Hughes, A. E. Lita, S. W. Nam, and J. E. Nordholt, "Long-distance decoy-state quantum key distribution in optical fiber," Phys. Rev. Lett. 98, 010503 (2007).
[CrossRef] [PubMed]

Hwang, W. Y.

W. Y. Hwang, "Quantum key distribution with high loss: towards global secure communication," Phys. Rev. Lett. 91, 057901 (2003).
[CrossRef] [PubMed]

Inoue, K.

K. Inoue, E. Waks and Y. Yamamoto, "Differential phase shift quantum key distribution," Phys. Rev. Lett. 89, 037902 (2002).
[CrossRef] [PubMed]

Kardynal, B. E.

Z. L. Yuan, B. E. Kardynal, A. W. Sharpe and A. J. Shields, "High speed single photon detection in the near infrared," Appl. Phys. Lett. 91, 041114 (2007).
[CrossRef]

Lita, A. E.

D. Rosenberg, J. W. Harrington, P. R. Rice, P. A. Hiskett, C. G. Peterson, R. J. Hughes, A. E. Lita, S. W. Nam, and J. E. Nordholt, "Long-distance decoy-state quantum key distribution in optical fiber," Phys. Rev. Lett. 98, 010503 (2007).
[CrossRef] [PubMed]

Lo, H. K.

H. K. Lo, X. Ma and K. Chen, "Decoy state quantum key distribution," Phys. Rev. Lett. 94, 230504 (2005).
[CrossRef] [PubMed]

X. Ma, B. Qi, Y. Zhao and H. K. Lo, "Practical decoy state for quantum key distribution," Phys. Rev. A 72, 012326 (2005).
[CrossRef]

D. Gottesman, H. K. Lo, N. Lütkenhaus and J. Preskill, "Security of quantum key distribution with imperfect devices," Quantum. Inf. Comput. 4, 325-360 (2004).

Lütkenhaus, N.

D. Gottesman, H. K. Lo, N. Lütkenhaus and J. Preskill, "Security of quantum key distribution with imperfect devices," Quantum. Inf. Comput. 4, 325-360 (2004).

G. Brassard, N. Lütkenhaus, T. Mor and B. C. Sanders, "Limitations on practical quantum cryptography," Phys. Rev. Lett. 85, 1330-1333 (2000).
[CrossRef] [PubMed]

Ma, H.-X.

C. Z. Peng, J. Zhang, D. Yang, W.-B. Gao, H.-X. Ma, H. Yin, H. P. Zeng, T. Yang, X.-B. Wang and J. W. Pan, "Experimental long-distance decoy-state quantum key distribution based on polarisation encoding," Phys. Rev. Lett. 98, 010505 (2007).
[CrossRef] [PubMed]

Ma, L. J.

A. Mink, X. Tang, L. J. Ma, T. Nakassis, B. Hershman, J. C. Bienfang, D. Su, R. Boisvert, C. W. Clark and C. J. Williams, "High speed quantum key distribution system supports one-time pad encryption of real-time video," Proc. SPIE 6244, 62440M (2006).
[CrossRef]

Ma, X.

H. K. Lo, X. Ma and K. Chen, "Decoy state quantum key distribution," Phys. Rev. Lett. 94, 230504 (2005).
[CrossRef] [PubMed]

X. Ma, B. Qi, Y. Zhao and H. K. Lo, "Practical decoy state for quantum key distribution," Phys. Rev. A 72, 012326 (2005).
[CrossRef]

Maeda, W.

Miki, S.

Mink, A.

A. Mink, X. Tang, L. J. Ma, T. Nakassis, B. Hershman, J. C. Bienfang, D. Su, R. Boisvert, C. W. Clark and C. J. Williams, "High speed quantum key distribution system supports one-time pad encryption of real-time video," Proc. SPIE 6244, 62440M (2006).
[CrossRef]

Mor, T.

G. Brassard, N. Lütkenhaus, T. Mor and B. C. Sanders, "Limitations on practical quantum cryptography," Phys. Rev. Lett. 85, 1330-1333 (2000).
[CrossRef] [PubMed]

Nakassis, T.

A. Mink, X. Tang, L. J. Ma, T. Nakassis, B. Hershman, J. C. Bienfang, D. Su, R. Boisvert, C. W. Clark and C. J. Williams, "High speed quantum key distribution system supports one-time pad encryption of real-time video," Proc. SPIE 6244, 62440M (2006).
[CrossRef]

Nam, S. W.

D. Rosenberg, J. W. Harrington, P. R. Rice, P. A. Hiskett, C. G. Peterson, R. J. Hughes, A. E. Lita, S. W. Nam, and J. E. Nordholt, "Long-distance decoy-state quantum key distribution in optical fiber," Phys. Rev. Lett. 98, 010503 (2007).
[CrossRef] [PubMed]

H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki and Y. Yamamoto, "Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors," Nat. Photonics 1, 343-348 (2007).
[CrossRef]

Nam, S.W.

Nambu, Y.

Nordholt, J. E.

D. Rosenberg, J. W. Harrington, P. R. Rice, P. A. Hiskett, C. G. Peterson, R. J. Hughes, A. E. Lita, S. W. Nam, and J. E. Nordholt, "Long-distance decoy-state quantum key distribution in optical fiber," Phys. Rev. Lett. 98, 010503 (2007).
[CrossRef] [PubMed]

Pan, J. W.

C. Z. Peng, J. Zhang, D. Yang, W.-B. Gao, H.-X. Ma, H. Yin, H. P. Zeng, T. Yang, X.-B. Wang and J. W. Pan, "Experimental long-distance decoy-state quantum key distribution based on polarisation encoding," Phys. Rev. Lett. 98, 010505 (2007).
[CrossRef] [PubMed]

Peng, C. Z.

C. Z. Peng, J. Zhang, D. Yang, W.-B. Gao, H.-X. Ma, H. Yin, H. P. Zeng, T. Yang, X.-B. Wang and J. W. Pan, "Experimental long-distance decoy-state quantum key distribution based on polarisation encoding," Phys. Rev. Lett. 98, 010505 (2007).
[CrossRef] [PubMed]

Peterson, C. G.

D. Rosenberg, J. W. Harrington, P. R. Rice, P. A. Hiskett, C. G. Peterson, R. J. Hughes, A. E. Lita, S. W. Nam, and J. E. Nordholt, "Long-distance decoy-state quantum key distribution in optical fiber," Phys. Rev. Lett. 98, 010503 (2007).
[CrossRef] [PubMed]

Preskill, J.

D. Gottesman, H. K. Lo, N. Lütkenhaus and J. Preskill, "Security of quantum key distribution with imperfect devices," Quantum. Inf. Comput. 4, 325-360 (2004).

Qi, B.

X. Ma, B. Qi, Y. Zhao and H. K. Lo, "Practical decoy state for quantum key distribution," Phys. Rev. A 72, 012326 (2005).
[CrossRef]

Rarity, J. G.

P. Townsend, J. G. Rarity and P. R. Tapster, "Single-photon interference in 10 km long optical fiber interferometer," Electron. Lett. 29, 634-639 (1993).
[CrossRef]

Rech, I.

Ribordy, G.

N. Gisin, G. Ribordy,W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145-195 (2002).
[CrossRef]

Rice, P. R.

D. Rosenberg, J. W. Harrington, P. R. Rice, P. A. Hiskett, C. G. Peterson, R. J. Hughes, A. E. Lita, S. W. Nam, and J. E. Nordholt, "Long-distance decoy-state quantum key distribution in optical fiber," Phys. Rev. Lett. 98, 010503 (2007).
[CrossRef] [PubMed]

Rosenberg, D.

D. Rosenberg, J. W. Harrington, P. R. Rice, P. A. Hiskett, C. G. Peterson, R. J. Hughes, A. E. Lita, S. W. Nam, and J. E. Nordholt, "Long-distance decoy-state quantum key distribution in optical fiber," Phys. Rev. Lett. 98, 010503 (2007).
[CrossRef] [PubMed]

Salvail, L.

C. H. Bennett, F. Bessette, G. Brassard, L. Salvail, and J. Smolin, "Experimental quantum cryptography," J. Cryptol. 5, 3-28 (1992).
[CrossRef]

Sanders, B. C.

G. Brassard, N. Lütkenhaus, T. Mor and B. C. Sanders, "Limitations on practical quantum cryptography," Phys. Rev. Lett. 85, 1330-1333 (2000).
[CrossRef] [PubMed]

Sasaki, M.

Scarani, V.

D. Stucki, N. Brunner, N. Gisin, V. Scarani and H. Zbinden, "Fast and simple one-way quantum key distribution," Appl. Phys. Lett. 87, 194108 (2005).
[CrossRef]

Sharpe, A. W.

Z. L. Yuan, A. R. Dixon, J. F. Dynes, A. W. Sharpe and A. J. Shields, "Gigahertz quantum key distribution with InGaAs avalanche photodiodes," Appl. Phys. Lett. 92, 201104 (2008).
[CrossRef]

J. F. Dynes, Z. L. Yuan, A. W. Sharpe and A. J. Shields, "A high speed, post-processing free, quantum random number generator," Appl. Phys. Lett. 93, 031109 (2008).
[CrossRef]

J. F. Dynes, Z. L. Yuan, A. W. Sharpe and A. J. Shields, "Practical quantum key distribution over 60 hours at an optical fiber distance of 20 km using weak and vacuum decoy pulses for enhanced security," Opt. Express 15, 8465 - 8471 (2007).
[CrossRef] [PubMed]

Z. L. Yuan, B. E. Kardynal, A. W. Sharpe and A. J. Shields, "High speed single photon detection in the near infrared," Appl. Phys. Lett. 91, 041114 (2007).
[CrossRef]

Z. L. Yuan, A. W. Sharpe and A. J. Shields, "Unconditionally secure quantum key distribution using decoy pulses," Appl. Phys. Lett. 90, 011118 (2007).
[CrossRef]

Shields, A. J.

Z. L. Yuan, A. R. Dixon, J. F. Dynes, A. W. Sharpe and A. J. Shields, "Gigahertz quantum key distribution with InGaAs avalanche photodiodes," Appl. Phys. Lett. 92, 201104 (2008).
[CrossRef]

J. F. Dynes, Z. L. Yuan, A. W. Sharpe and A. J. Shields, "A high speed, post-processing free, quantum random number generator," Appl. Phys. Lett. 93, 031109 (2008).
[CrossRef]

Z. L. Yuan, B. E. Kardynal, A. W. Sharpe and A. J. Shields, "High speed single photon detection in the near infrared," Appl. Phys. Lett. 91, 041114 (2007).
[CrossRef]

J. F. Dynes, Z. L. Yuan, A. W. Sharpe and A. J. Shields, "Practical quantum key distribution over 60 hours at an optical fiber distance of 20 km using weak and vacuum decoy pulses for enhanced security," Opt. Express 15, 8465 - 8471 (2007).
[CrossRef] [PubMed]

Z. L. Yuan, A. W. Sharpe and A. J. Shields, "Unconditionally secure quantum key distribution using decoy pulses," Appl. Phys. Lett. 90, 011118 (2007).
[CrossRef]

Z. L. Yuan and A. J. Shields, "Continuous operation of a one-way quantum key distribution system over installed telecom fibre," Opt. Express 13, 660-665 (2005).
[CrossRef] [PubMed]

C. Gobby, Z. L. Yuan and A. J. Shields, "Quantum key distribution over 122 km telecom fiber," Appl. Phys. Lett. 84, 3762-3764 (2002).
[CrossRef]

Smolin, J.

C. H. Bennett, F. Bessette, G. Brassard, L. Salvail, and J. Smolin, "Experimental quantum cryptography," J. Cryptol. 5, 3-28 (1992).
[CrossRef]

Stucki, D.

D. Stucki, N. Brunner, N. Gisin, V. Scarani and H. Zbinden, "Fast and simple one-way quantum key distribution," Appl. Phys. Lett. 87, 194108 (2005).
[CrossRef]

Su, D.

A. Mink, X. Tang, L. J. Ma, T. Nakassis, B. Hershman, J. C. Bienfang, D. Su, R. Boisvert, C. W. Clark and C. J. Williams, "High speed quantum key distribution system supports one-time pad encryption of real-time video," Proc. SPIE 6244, 62440M (2006).
[CrossRef]

Tajima, A.

Takahashi, S.

Takesue, H.

H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki and Y. Yamamoto, "Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors," Nat. Photonics 1, 343-348 (2007).
[CrossRef]

Tamaki, K.

H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki and Y. Yamamoto, "Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors," Nat. Photonics 1, 343-348 (2007).
[CrossRef]

Tanaka, A.

Tang, X.

A. Mink, X. Tang, L. J. Ma, T. Nakassis, B. Hershman, J. C. Bienfang, D. Su, R. Boisvert, C. W. Clark and C. J. Williams, "High speed quantum key distribution system supports one-time pad encryption of real-time video," Proc. SPIE 6244, 62440M (2006).
[CrossRef]

Tapster, P. R.

P. Townsend, J. G. Rarity and P. R. Tapster, "Single-photon interference in 10 km long optical fiber interferometer," Electron. Lett. 29, 634-639 (1993).
[CrossRef]

Tittel, W.

N. Gisin, G. Ribordy,W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145-195 (2002).
[CrossRef]

Tomita, A.

Townsend, P.

P. Townsend, J. G. Rarity and P. R. Tapster, "Single-photon interference in 10 km long optical fiber interferometer," Electron. Lett. 29, 634-639 (1993).
[CrossRef]

Townsend, P. D.

Waks, E.

K. Inoue, E. Waks and Y. Yamamoto, "Differential phase shift quantum key distribution," Phys. Rev. Lett. 89, 037902 (2002).
[CrossRef] [PubMed]

Wang, X. B.

X. B. Wang, "Beating the photon-number-splitting attack in practical quantum cryptography," Phys. Rev. Lett. 94, 230503 (2005).
[CrossRef] [PubMed]

X. B. Wang, "Decoy-state protocol for quantum cryptography with four different intensities of coherent light," Phys. Rev. A 72, 012322 (2005).
[CrossRef]

Wang, X.-B.

C. Z. Peng, J. Zhang, D. Yang, W.-B. Gao, H.-X. Ma, H. Yin, H. P. Zeng, T. Yang, X.-B. Wang and J. W. Pan, "Experimental long-distance decoy-state quantum key distribution based on polarisation encoding," Phys. Rev. Lett. 98, 010505 (2007).
[CrossRef] [PubMed]

Wang, Z.

Williams, C. J.

A. Mink, X. Tang, L. J. Ma, T. Nakassis, B. Hershman, J. C. Bienfang, D. Su, R. Boisvert, C. W. Clark and C. J. Williams, "High speed quantum key distribution system supports one-time pad encryption of real-time video," Proc. SPIE 6244, 62440M (2006).
[CrossRef]

Yamamoto, Y.

H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki and Y. Yamamoto, "Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors," Nat. Photonics 1, 343-348 (2007).
[CrossRef]

K. Inoue, E. Waks and Y. Yamamoto, "Differential phase shift quantum key distribution," Phys. Rev. Lett. 89, 037902 (2002).
[CrossRef] [PubMed]

Yang, D.

C. Z. Peng, J. Zhang, D. Yang, W.-B. Gao, H.-X. Ma, H. Yin, H. P. Zeng, T. Yang, X.-B. Wang and J. W. Pan, "Experimental long-distance decoy-state quantum key distribution based on polarisation encoding," Phys. Rev. Lett. 98, 010505 (2007).
[CrossRef] [PubMed]

Yang, T.

C. Z. Peng, J. Zhang, D. Yang, W.-B. Gao, H.-X. Ma, H. Yin, H. P. Zeng, T. Yang, X.-B. Wang and J. W. Pan, "Experimental long-distance decoy-state quantum key distribution based on polarisation encoding," Phys. Rev. Lett. 98, 010505 (2007).
[CrossRef] [PubMed]

Yin, H.

C. Z. Peng, J. Zhang, D. Yang, W.-B. Gao, H.-X. Ma, H. Yin, H. P. Zeng, T. Yang, X.-B. Wang and J. W. Pan, "Experimental long-distance decoy-state quantum key distribution based on polarisation encoding," Phys. Rev. Lett. 98, 010505 (2007).
[CrossRef] [PubMed]

Yoshino, K.

Yuan, Z. L.

J. F. Dynes, Z. L. Yuan, A. W. Sharpe and A. J. Shields, "A high speed, post-processing free, quantum random number generator," Appl. Phys. Lett. 93, 031109 (2008).
[CrossRef]

Z. L. Yuan, A. R. Dixon, J. F. Dynes, A. W. Sharpe and A. J. Shields, "Gigahertz quantum key distribution with InGaAs avalanche photodiodes," Appl. Phys. Lett. 92, 201104 (2008).
[CrossRef]

Z. L. Yuan, A. W. Sharpe and A. J. Shields, "Unconditionally secure quantum key distribution using decoy pulses," Appl. Phys. Lett. 90, 011118 (2007).
[CrossRef]

Z. L. Yuan, B. E. Kardynal, A. W. Sharpe and A. J. Shields, "High speed single photon detection in the near infrared," Appl. Phys. Lett. 91, 041114 (2007).
[CrossRef]

J. F. Dynes, Z. L. Yuan, A. W. Sharpe and A. J. Shields, "Practical quantum key distribution over 60 hours at an optical fiber distance of 20 km using weak and vacuum decoy pulses for enhanced security," Opt. Express 15, 8465 - 8471 (2007).
[CrossRef] [PubMed]

Z. L. Yuan and A. J. Shields, "Continuous operation of a one-way quantum key distribution system over installed telecom fibre," Opt. Express 13, 660-665 (2005).
[CrossRef] [PubMed]

C. Gobby, Z. L. Yuan and A. J. Shields, "Quantum key distribution over 122 km telecom fiber," Appl. Phys. Lett. 84, 3762-3764 (2002).
[CrossRef]

Zbinden, H.

D. Stucki, N. Brunner, N. Gisin, V. Scarani and H. Zbinden, "Fast and simple one-way quantum key distribution," Appl. Phys. Lett. 87, 194108 (2005).
[CrossRef]

N. Gisin, G. Ribordy,W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145-195 (2002).
[CrossRef]

Zeng, H. P.

C. Z. Peng, J. Zhang, D. Yang, W.-B. Gao, H.-X. Ma, H. Yin, H. P. Zeng, T. Yang, X.-B. Wang and J. W. Pan, "Experimental long-distance decoy-state quantum key distribution based on polarisation encoding," Phys. Rev. Lett. 98, 010505 (2007).
[CrossRef] [PubMed]

Zhang, J.

C. Z. Peng, J. Zhang, D. Yang, W.-B. Gao, H.-X. Ma, H. Yin, H. P. Zeng, T. Yang, X.-B. Wang and J. W. Pan, "Experimental long-distance decoy-state quantum key distribution based on polarisation encoding," Phys. Rev. Lett. 98, 010505 (2007).
[CrossRef] [PubMed]

Zhang, Q.

H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki and Y. Yamamoto, "Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors," Nat. Photonics 1, 343-348 (2007).
[CrossRef]

Zhao, Y.

X. Ma, B. Qi, Y. Zhao and H. K. Lo, "Practical decoy state for quantum key distribution," Phys. Rev. A 72, 012326 (2005).
[CrossRef]

Appl. Phys. Lett.

C. Gobby, Z. L. Yuan and A. J. Shields, "Quantum key distribution over 122 km telecom fiber," Appl. Phys. Lett. 84, 3762-3764 (2002).
[CrossRef]

Z. L. Yuan, A. R. Dixon, J. F. Dynes, A. W. Sharpe and A. J. Shields, "Gigahertz quantum key distribution with InGaAs avalanche photodiodes," Appl. Phys. Lett. 92, 201104 (2008).
[CrossRef]

D. Stucki, N. Brunner, N. Gisin, V. Scarani and H. Zbinden, "Fast and simple one-way quantum key distribution," Appl. Phys. Lett. 87, 194108 (2005).
[CrossRef]

Z. L. Yuan, A. W. Sharpe and A. J. Shields, "Unconditionally secure quantum key distribution using decoy pulses," Appl. Phys. Lett. 90, 011118 (2007).
[CrossRef]

Z. L. Yuan, B. E. Kardynal, A. W. Sharpe and A. J. Shields, "High speed single photon detection in the near infrared," Appl. Phys. Lett. 91, 041114 (2007).
[CrossRef]

J. F. Dynes, Z. L. Yuan, A. W. Sharpe and A. J. Shields, "A high speed, post-processing free, quantum random number generator," Appl. Phys. Lett. 93, 031109 (2008).
[CrossRef]

Electron. Lett.

P. Townsend, J. G. Rarity and P. R. Tapster, "Single-photon interference in 10 km long optical fiber interferometer," Electron. Lett. 29, 634-639 (1993).
[CrossRef]

J. Cryptol.

C. H. Bennett, F. Bessette, G. Brassard, L. Salvail, and J. Smolin, "Experimental quantum cryptography," J. Cryptol. 5, 3-28 (1992).
[CrossRef]

Nat. Photonics

H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki and Y. Yamamoto, "Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors," Nat. Photonics 1, 343-348 (2007).
[CrossRef]

Opt. Commun.

M. Dusek, O. Haderka and M. Hendrych,"Generalized beam-splitting attack in quantum cryptography with dim coherent states," Opt. Commun. 169, 103-108 (1999).
[CrossRef]

Opt. Express

Phys. Rev. A

X. Ma, B. Qi, Y. Zhao and H. K. Lo, "Practical decoy state for quantum key distribution," Phys. Rev. A 72, 012326 (2005).
[CrossRef]

X. B. Wang, "Decoy-state protocol for quantum cryptography with four different intensities of coherent light," Phys. Rev. A 72, 012322 (2005).
[CrossRef]

Phys. Rev. Lett.

W. Y. Hwang, "Quantum key distribution with high loss: towards global secure communication," Phys. Rev. Lett. 91, 057901 (2003).
[CrossRef] [PubMed]

X. B. Wang, "Beating the photon-number-splitting attack in practical quantum cryptography," Phys. Rev. Lett. 94, 230503 (2005).
[CrossRef] [PubMed]

G. Brassard, N. Lütkenhaus, T. Mor and B. C. Sanders, "Limitations on practical quantum cryptography," Phys. Rev. Lett. 85, 1330-1333 (2000).
[CrossRef] [PubMed]

H. K. Lo, X. Ma and K. Chen, "Decoy state quantum key distribution," Phys. Rev. Lett. 94, 230504 (2005).
[CrossRef] [PubMed]

D. Rosenberg, J. W. Harrington, P. R. Rice, P. A. Hiskett, C. G. Peterson, R. J. Hughes, A. E. Lita, S. W. Nam, and J. E. Nordholt, "Long-distance decoy-state quantum key distribution in optical fiber," Phys. Rev. Lett. 98, 010503 (2007).
[CrossRef] [PubMed]

C. Z. Peng, J. Zhang, D. Yang, W.-B. Gao, H.-X. Ma, H. Yin, H. P. Zeng, T. Yang, X.-B. Wang and J. W. Pan, "Experimental long-distance decoy-state quantum key distribution based on polarisation encoding," Phys. Rev. Lett. 98, 010505 (2007).
[CrossRef] [PubMed]

K. Inoue, E. Waks and Y. Yamamoto, "Differential phase shift quantum key distribution," Phys. Rev. Lett. 89, 037902 (2002).
[CrossRef] [PubMed]

Proc. SPIE

A. Mink, X. Tang, L. J. Ma, T. Nakassis, B. Hershman, J. C. Bienfang, D. Su, R. Boisvert, C. W. Clark and C. J. Williams, "High speed quantum key distribution system supports one-time pad encryption of real-time video," Proc. SPIE 6244, 62440M (2006).
[CrossRef]

Quantum. Inf. Comput.

D. Gottesman, H. K. Lo, N. Lütkenhaus and J. Preskill, "Security of quantum key distribution with imperfect devices," Quantum. Inf. Comput. 4, 325-360 (2004).

Rev. Mod. Phys.

N. Gisin, G. Ribordy,W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145-195 (2002).
[CrossRef]

Other

C. H. Bennett and G. Brassard, "Quantum cryptography: public key distribution and coin tossing," Proceedings of the IEEE International Conference on Computers, Systems and Signal Processing, Bangalore, India, 1984, pp. 175-179.

W. Stallings, Cryptography and network security, 3rd ed. (Prentice and Hall, New Jersey, 2003).

European Integrated Project SECOQC, http://www.secoqc.net.

Our time-tagging electronics record each photon with a 32-bit number to represent its arrival time. Due to restriction in the data bandwidth at around 160 Mbit/s per channel, for transferring photon information into computer memory, each channel can cope with only 5 million photons per second at most.

V. Scarani, H. Bechmann-Pasquinucci, N. J. Cerf, M. Dusek, N. Lutkenhaus and M. Peev, "A framework for practical quantum cryptography," arXiv: 0802.4155v1 (2008).

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Figures (3)

Fig. 1.
Fig. 1.

Schematic of QKD system. [P] denotes a phase modulator, [B] a polarising beam splitter/combiner, [A] an attenuator, [M] an optical power meter, [C] a polarization controller and [D] InGaAs APD. All the modulating optics are driven by stand-alone gigahertz pattern generators with pre-loaded pseudo-random patterns.

Fig. 2.
Fig. 2.

Self-difference mode operation of an InGaAs APD. (a) Schematic for an APD in self-differencing mode. [S] is a 50:50 electrical signal splitter, [D] a subtractive combiner; Co-axial cables connecting the splitter and combiner are made with precise lengths so that the time delay between them corresponds to one APD gating clock period. The APD raw output signal is dominated by the periodic capacitive response, as shown in the inset. (b) A SD output recorded by an oscilloscope. The arrows indicate well discriminated avalanches. (c) Histogram of photon arrival times obtained using the output of the SD circuit. (d) A comparison of histograms of photon arrivals obtained with the same APD under conventional gated Geiger mode operation (blue line) or SD mode (black line). For both measurements, the photon detection efficiency was set to 10%. The red circles represent a Gaussian fit for histograms obtained with the SD circuit, giving a full width at half maximum of 50 ps.

Fig. 3.
Fig. 3.

Decoy QKD experimental results. Raw (filled squares), secure (open squares) key rate, and the QBER (solid circles). Theoretical simulations are also shown for raw (solid lines), secure (dashed lines) key rates and the QBER (dotted line). In simulations, Bob’s detection efficiency is set to 5% (corresponding 10% of detector efficiency), detector dark count rate of 6.8×10-6 per gate and afterpulse rate 4.7%, and a QBER of 0.3% due to optical misalignment. All simulation parameters used are consistent with experimental results.

Tables (1)

Tables Icon

Table 1. Summary of parameters and results for 20-km decoy QKD experiment. 10 standard deviations are also shown for Q µ , Q ν 1, Q ν 2 and ε µ .

Equations (4)

Equations on this page are rendered with MathJax. Learn more.

Q 1 Q 1 L = μ 2 e μ μ ν 1 μ ν 2 ν 1 2 + ν 2 2 [ Q ν 1 e ν 1 Q ν 2 e ν 2 ν 1 2 ν 2 2 μ 2 ( Q μ e μ Y 0 L ) ] .
ε 1 ε 1 U = ε μ Q μ e μ 1 2 Y 0 L Q 1 L e μ ,
Y 0 Y 0 L = ν 1 Q ν 2 e ν 2 ν 2 Q ν 1 e ν 1 ν 1 ν 2
R sec ure = 1 2 N μ { Q μ f EC H 2 ( ε μ ) + Q 1 L [ 1 H 2 ( ε 1 U ) ] } t

Metrics