Free-space quantum key distribution in daylight

Abstract Quantum cryptography is an emerging technology in which two parties may simultaneously generate shared, secret cryptographic key material using the transmission of quantum states of light. The security of these transmissions is based on the inviolability of the laws of quantum mechanics and information-theoretically secure post-processing methods. An adversary can neither successfully tap the quantum transmissions, nor evade detection, owing to Heisenberg's uncertainty principle. In this paper we describe the theory of quantum cryptography, and the most recent results from our experimental free-space system with which we have demonstrated for the first time the feasibility of quantum key generation over a point-to-point outdoor atmospheric path in daylight. We achieved a transmission distance of 0.5 km, which was limited only by the length of the test range. Our results provide strong evidence that cryptographic key material could be generated on demand between a ground station and a satellite (or between two satellites), allowing a satellite to be securely re-keyed in orbit. We present a feasibility analysis of surface-to-satellite quantum key generation.

[1]  J. Clauser.  Experimental distinction between the quantum and classical field - theoretic predictions for the pho , 1973 .

[2]  Gilles Brassard,et al.  Experimental quantum cryptography: the dawn of a new era for quantum cryptography: the experimental prototype is working] , 1989, SIGACT News.

[3]  John Rarity,et al.  Daylight demonstration of low-light-level communication system using correlated photon pairs , 1991 .

[4]  G. L. Morgan,et al.  Quantum Cryptography over Underground Optical Fibers , 1996, CRYPTO.

[5]  Richard Hughes,et al.  Quantum cryptography takes to the air , 1999 .

[6]  W. Wootters,et al.  A single quantum cannot be cloned , 1982, Nature.

[7]  James R. Lesh,et al.  Overview of the Ground-to-Orbit Lasercom Demonstration (GOLD) , 1997, Photonics West.

[8]  Richard J. Hughes,et al.  Secure communications using quantum cryptography , 1997, Defense, Security, and Sensing.

[9]  Gilles Brassard,et al.  Secret-Key Reconciliation by Public Discussion , 1994, EUROCRYPT.

[10]  Ekert,et al.  Quantum cryptography based on Bell's theorem. , 1991, Physical review letters.

[11]  Larry Carter,et al.  New Hash Functions and Their Use in Authentication and Set Equality , 1981, J. Comput. Syst. Sci..

[12]  C. M. Simmons,et al.  Practical free-space quantum key distribution over 1 km , 1998 .

[13]  Qingji Wang,et al.  Rb 780 nm Faraday anomalous dispersion optical filter in a strong magnetic field , 1993 .

[14]  J. Rarity,et al.  Single photon interference in 10 km long optical fibre interferometer , 1993 .

[15]  J. Franson,et al.  Quantum cryptography in free space. , 1996, Optics letters.

[16]  Horace P. Yuen,et al.  Quantum amplifiers, quantum duplicators and quantum cryptography , 1996 .

[17]  Charles H. Bennett,et al.  Quantum cryptography using any two nonorthogonal states. , 1992, Physical review letters.

[18]  Ekert,et al.  Eavesdropping on quantum-cryptographical systems. , 1994, Physical review. A, Atomic, molecular, and optical physics.

[19]  J. Franson,et al.  Quantum cryptography using optical fibers. , 1994, Applied optics.

[20]  Richard J. Hughes,et al.  FREE-SPACE QUANTUM-KEY DISTRIBUTION , 1998, quant-ph/9801006.

[21]  P R Tapster,et al.  Range measurement photon by photon , 1989 .

[22]  Ueli Maurer,et al.  Generalized privacy amplification , 1994, Proceedings of 1994 IEEE International Symposium on Information Theory.

[23]  N. Gisin,et al.  Experimental Demonstration of Quantum Cryptography Using Polarized Photons in Optical Fibre over More than 1 km , 1993 .

[24]  Sherman Karp,et al.  Optical Communications , 1976 .