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## Quantum cryptography (2002)

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- [arxiv.org]
- [www.gapoptic.unige.ch]
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- [www.gap-optique.unige.ch]
- [www.hep.princeton.edu]
- [www.gapoptic.unige.ch]
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### Other Repositories/Bibliography

Venue: | Rev. Mod. Phys |

Citations: | 181 - 6 self |

### Citations

3469 | New Directions in Cryptography - Diffie, Hellman - 1976 |

1152 |
Can quantum mechanical description of physical reality be considered complete?”, Phys
- Einstein, Podolsky, et al.
- 1935
(Show Context)
Citation Context ... fascinating to realize that QC lies at the intersection of quantum mechanics and information theory and that, moreover, the tension between quantum mechanics and relativity – the famous EPR paradox (=-=Einstein et al. 1935-=-) – is closely connected to the security of QC. Let us add a further point for the young physicists. Contrary to laser and semiconductor physics, which are manifestations of quantum physics at the ens... |

960 | Quantum cryptography: Public key distribution and coin tossing - Bennett, Brassard - 1984 |

846 | Quantum Theory, the Church-Turing Principle and the Universal Quantum Computer - Deutsch - 1985 |

740 |
Broadcast Channels with Confidential Messages
- Csiszar, Korner
- 1978
(Show Context)
Citation Context ...between Alice and Bob, S(α, β||ǫ), are not yet known. However, a useful lower bound is given by the difference between Alice and Bob’s mutual Shannon information I(α, β) and Eve’s mutual information (=-=Csiszár and Körner 1978-=-, and theorem 1 in section VI G): S(α, β||ǫ) ≥ max{I(α, β) − I(α, ǫ), I(α, β) − I(β, ǫ)} (8) Intuitively, this result states that secure key distillation (Bennett et al. 1992a) is possible whenever Bo... |

643 | Teleporting an unknown quantum state via dual classical and EPR channels, Phys - Bennett, Brassard, et al. - 1993 |

453 |
Proposed experiment to test local hidden-variable theories
- Clauser, Horne, et al.
- 1969
(Show Context)
Citation Context ...t than the classical privacy amplification ones. F. Connection to Bell inequality There is an intriguing connection between the above tight bound (69) and the CHSH form of Bell inequality (Bell 1964, =-=Clauser et al. 1969-=-, Clauser and Shimony 1978, Zeilinger 1999): S ≡ E(a, b) + E(a, b ′ ) + E(a ′ , b) − E(a ′ , b ′ ) ≤ 2 (70) where E(a, b) is the correlation between Alice and Bob’s data when measuring σa ⊗1 and 1⊗σb,... |

409 | Quantum cryptography based on Bell’s theorem, Phys - Ekert - 1991 |

321 | Generalized privacy amplification
- Bennett, Brassard, et al.
- 1995
(Show Context)
Citation Context ...acy amplification appears in Bennett, Brassard and Robert (1988). It was then extended in collaboration with C. Crépeau and U. Maurer from the University of Montreal and the ETH Zürich, respectively (=-=Bennett et al. 1995-=-, see also Bennett et al. 1992a). Interestingly, this work motivated by QC found applications in standard information-based cryptography (Maurer 1993, Maurer and Wolf 1999). Assume that such a joint p... |

320 |
Experimental test of Bell’s inequalities using time- varying analyzers
- Aspect, Dalibard, et al.
- 1982
(Show Context)
Citation Context ...n splitting attacks (see section VI J). 42 This definition of quantum cryptography applies to the famous experiment by Aspect and his co-workers testing Bell inequalities with time varying analyzers (=-=Aspect et al., 1982-=-). QC had however not yet been invented. It also applies to the more recent experiments closing the locality loopholes, like the one performed in Innsbruck using fast polarization modulators (Weihs et... |

301 | Quantal phase factors accompanying adiabatic changes - Berry |

261 | Experimental quantum cryptography - Bennett, Bessette, et al. - 1992 |

260 |
On the Problem of Hidden Variables in Quantum Mechanics
- Bell
- 1966
(Show Context)
Citation Context ...sted to base the security of this 2-qubit protocol on Bell’s inequality, an inequality which demonstrates that some correlation predicted by quantum mechanics can’t be reproduced by any local theory (=-=Bell 1964-=-). For this, Alice and Bob have a third choice of basis (see Fig. 4). In this way the probability that they happen to choose the same basis is reduced from 1 2 2 to 9 , but at the same time as they es... |

237 |
Privacy amplification by public discussion
- Bennett, Brassard, et al.
- 1988
(Show Context)
Citation Context ...otocol. 5. Advantage distillation QC has triggered and still triggers research in classical information theory. The best known example is probably the development of privacy amplification algorithms (=-=Bennett et al. 1988-=- and 1995). This in turn triggered the development of new cryptosystems based on weak but classical signals, emitted for instance by satellites (Maurer 1993) 11 . These new developments required secre... |

192 |
Quantum cryptography using any two nonorthogonal states
- Bennett
- 1992
(Show Context)
Citation Context ... more transparent one, see section VI H). The two-state protocol can also be implemented using an interference between a macroscopic bright pulse and a dim pulse with less than one photon on average (=-=Bennett, 1992-=-). The presence of the bright pulse makes this protocol specially resistant to eavesdropping, even in settings with high attenuation. Indeed Bob can monitor the bright pulses, to make sure that Eve do... |

156 | Secret-key reconciliation by public discussions
- Brassard, Salvail
- 1994
(Show Context)
Citation Context ...then the probability that she guesses correctly the value of the XOR is only of 0.6 2 + 0.4 2 = 52%. This process would have to be repeated several times; more efficient algorithms use larger blocks (=-=Brassard and Salvail 1993-=-). The error correction and privacy amplification algorithms sketched above are purely classical algorithms. This illustrates that QC is a truly interdisciplinary field. Actually, the above presentati... |

111 | Bell’s theorem. Experimental tests and implications
- Clauser, Shimony
- 1978
(Show Context)
Citation Context ...privacy amplification ones. F. Connection to Bell inequality There is an intriguing connection between the above tight bound (69) and the CHSH form of Bell inequality (Bell 1964, Clauser et al. 1969, =-=Clauser and Shimony 1978-=-, Zeilinger 1999): S ≡ E(a, b) + E(a, b ′ ) + E(a ′ , b) − E(a ′ , b ′ ) ≤ 2 (70) where E(a, b) is the correlation between Alice and Bob’s data when measuring σa ⊗1 and 1⊗σb, where σa denotes an obser... |

111 | Quantum cryptography without Bell’s theorem - Bennett, Brassard, et al. - 1992 |

58 | A proof of the security of quantum key distribution - Biham, Boyer, et al. - 2000 |

58 | Optimal Eavesdropping in Quantum Cryptography
- Fuchs, Gisin, et al.
- 1997
(Show Context)
Citation Context ...usly Robert Griffiths and his student Chi-Sheng Niu derived it under very general conditions and Nicolas Gisin using the symmetry argument used here. These 5 authors joined efforts in a common paper (=-=Fuchs et al. 1997-=-). The result of this section is thus also valid without this symmetry assumption. 38 U| ↓, 0〉 = | ↓〉 ⊗ φ↓ + | ↑〉 ⊗ θ↓ (48) where the 4 states φ↑, φ↓, θ↑ and θ↓ belong to Eve’s probe Hilbert space HEv... |

57 |
Practical free-space quantum key distribution over 1 km, Phys
- Buttler, Hughes, et al.
- 1998
(Show Context)
Citation Context ... fluorescent lighting and 75 m outdoor in bright daylight without excessive QBER. Hughes and his team were the first to exchange a key over more than one kilometer under outdoor nighttime conditions (=-=Buttler et al. 1998-=-, and Hughes et al. 2000a). More recently, they even improved their system to reach a distance of 1.6 km under daylight conditions (Buttler et al. 2000). Finally Rarity and his coworkers performed a s... |

56 | Quantum copying: Beyond the no-cloning theorem - Bužek, Hillery - 1996 |

47 |
Avalanche photodiodes and quenching circuits for single-photon detection
- Cova, Ghioni, et al.
- 1956
(Show Context)
Citation Context ...d photon to trigger an electron avalanche consisting of thousands of carriers. To reset the diode, this macroscopic current must be quenched – the emission of charges stopped and the diode recharged (=-=Cova et al. 1996-=-). Three main possibilities exist: • In passive-quenching circuits, a large (50-500 kΩ) resistor is connected in series with the APD (see e.g. Brown et al. 1986). This causes a decrease of the voltage... |

41 |
Communication by EPR Devices , Phys
- Dieks
- 1982
(Show Context)
Citation Context ..., keeping a copy for herself. 2. No cloning theorem Following Wootters and Zurek (1982) it is easy to prove that perfect copying is impossible in the quantum world (see also Milonni and Hardies 1982, =-=Dieks 1982-=-, and the anticipating intuition by Wigner in 1961). Let ψ denote the original state of the qubit, |b〉 the blank copy 8 and denote |0〉 ∈ HQCM the initial state of Eve’s “quantum copy machine”, where t... |

36 |
Optimal eavesdropping in quantum cryptography with six states
- Bruss
- 1998
(Show Context)
Citation Context ...he four-states protocol in 1995. 2. 6-state protocol While two states are enough and four states are standard, a 6-state protocol respects much more the symmetry of the qubit state space, see Fig. 2 (=-=Bruss 1998-=-, Bechmann-Pasquinucci and Gisin 1999). The 6 states constitute 3 bases, hence the probability that Alice and Bob chose the same basis is only of 1 3 . But the symmetry of this protocol greatly simpli... |

34 | Quantum cryptography with 3-state systems
- Bechmann-Pasquinucci, Peres
(Show Context)
Citation Context ...nal key rate, after error correction and privacy amplification, is higher or not. Another variation consists in using quantum systems of dimension larger than 2 (Bechmann-Pasquinucci and Tittel 2000, =-=Bechmann-Pasquinucci and Peres 2000-=-, Bourennane et al. 2001a). Again, the practical value of this idea has not yet been fully determined. A third variation worth mentioning is due to Goldenberg and Vaidman, from Tel-Aviv University (19... |

33 |
G.M.!Palma, “Practical quantum cryptography based on twophoton interferometry
- Ekert, Rarity
- 1992
(Show Context)
Citation Context ...lity to use entangled photon pairs for quantum cryptography was first proposed by Ekert in 1991. In a subsequent paper, he investigated, with other researchers, the feasibility of a practical system (=-=Ekert et al., 1992-=-). Although all tests of Bell inequalities (for a review, see for example, Zeilinger 1999) can be seen as experiments of quantum cryptography, systems specifically designed to meet the special require... |

28 |
S.: Optimal quantum cloning machines
- Gisin, Massar
- 1997
(Show Context)
Citation Context ... The corresponding fidelity is: F = 3 2 + 1 2 3 � = 5 6 = 2P↑ + 1 2 1 3 (21) (22) which is precisely the optimal fidelity compatible with quantum mechanics (Buˇzek and Hillery 1996, Bruss et al 1998, =-=Gisin and Massar 1997-=-). In other words, if we start with a single photon in an arbitrary state, and pass it through an amplifier, then due to the effect of spontaneous emission the fidelity of the state exiting the amplif... |

26 | Security of quantum cryptography against collective attacks - Biham, Mor - 1997 |

24 | Quantum cryptography using larger alphabets
- Bechmann-Pasquinucci, Tittel
(Show Context)
Citation Context ...uently, it is not clear whether the final key rate, after error correction and privacy amplification, is higher or not. Another variation consists in using quantum systems of dimension larger than 2 (=-=Bechmann-Pasquinucci and Tittel 2000-=-, Bechmann-Pasquinucci and Peres 2000, Bourennane et al. 2001a). Again, the practical value of this idea has not yet been fully determined. A third variation worth mentioning is due to Goldenberg and ... |

24 |
Pulsed energy-time entangled twin-photon source for quantum communication Phys
- Brendel, Tittel, et al.
- 1999
(Show Context)
Citation Context ... equally well implemented with only two states on the equator and the two other ones on the poles. In this section, we present a system exploiting such a set of states. Proposed by our group in 1999 (=-=Brendel et al., 1999-=-), the scheme follows in principle the Franson configuration described in the context of phase coding. However, it is based on a pulsed source emitting entangled photons in so-called energy-time Bell ... |

24 | Practical quantum cryptography: A comprehensive analysis (part one),” 2000. [Online]. Available: arXiv.org:quant-ph/0009027 - Gilbert, Hamrick |

23 |
Daylight quantum key distribution over 1.6 km, Phys
- Buttler, Hughes, et al.
- 2000
(Show Context)
Citation Context ...ne kilometer under outdoor nighttime conditions (Buttler et al. 1998, and Hughes et al. 2000a). More recently, they even improved their system to reach a distance of 1.6 km under daylight conditions (=-=Buttler et al. 2000-=-). Finally Rarity and his coworkers performed a similar experiment where they exchanged a key over a distance of 1.9 km under nighttime conditions (Gorman et al. 2000). 40 Remember that Bennett and hi... |

22 |
A local hidden variable model of quantum correlation exploiting the detection loophole
- Gisin, Gisin
- 1999
(Show Context)
Citation Context ...ingly, one of the most subtle loopholes in all present day tests of Bell inequality, the detection loophole, can be exploited to produce a purely classical software mimicking all quantum correlation (=-=Gisin and Gisin 1999-=-). This illustrates once again how close practical issues in QC are to philosophical debates about the foundations of quantum physics! Finally, one has to assume that Alice and Bob are perfectly isola... |

22 | Bounds on information and the security of quantum cryptography - Biham, Mor - 1997 |

19 |
Quantum repeaters based on entanglement purification, Phys
- Dür, H, et al.
- 1999
(Show Context)
Citation Context ...o the detectors’ noise there is noise due to decoherence, then the above idea can be extended, using entanglement purification. This is essentially the idea of quantum repeaters (Briegel et al. 1998, =-=Dur et al. 1999-=-). 21 IV. EXPERIMENTAL QUANTUM CRYPTOGRAPHY WITH FAINT LASER PULSES Experimental quantum key distribution was demonstrated for the first time in 1989 (it was published only in 1992 by Bennett et al. 1... |

17 | Quantum Key Distribution Using Multilevel Encoding: Security Analysis - Bourennane, Karlsson, et al. - 2002 |

16 |
Experimental test of local hidden variable theories
- Freedman, Clauser
- 1972
(Show Context)
Citation Context ...connection to the famous EPR paradox (Einstein, Podolski and Rosen 1935): the initially philosophical debate turned to theoretical physics with Bell’s inequality (1964), then to experimental physics (=-=Freedmann and Clauser 1972-=-, Fry and Thompson 1976, and Aspect, Dalibard and Roger 1982), and is now – thanks to Ekert’s ingenious idea – part of applied physics. The idea consists in replacing the quantum channel carrying qubi... |

16 | Quantum State Disturbance vs. Information Gain: Uncertainty Relations for Quantum Information,” Phys - Fuchs, Peres - 1996 |

15 |
Photon antibunching in the fluorescence of individual color centers in diamond
- Brouri, Beveratos, et al.
- 2000
(Show Context)
Citation Context ...oom temperature. Promising candidates, however, are nitrogen-vacancy centers in diamond, a substitutional nitrogen atom with a vacancy trapped at an adjacent lattice position (Kurtsiefer et al. 2000, =-=Brouri et al. 2000-=-). It is possible to excite individual nitrogen atoms with a 532 nm laser beam, which will subsequently emit a fluorescence photon around 700 nm (12ns decay time). The fluorescence exhibits strong pho... |

15 |
Faint laser quantum key distribution: eavesdropping exploiting multiphoton pulses
- Félix, Gisin, et al.
(Show Context)
Citation Context ... unrealistic assumptions. In this section, following N. Lütkenhaus (2000) and M. Dusek et al (2000), we briefly comment on a realistic attack, also exploiting the multiphoton pulses (for details, see =-=Felix et al. 2001-=-, where this and another examples are presented). Assume that Eve splits all pulses in two, analysing each half in one of the two bases, using photon counting devices able to distinguish pulses with 0... |

13 | Quantum public key distribution system - Bennett, Brassard - 1985 |

13 | A brief review on the impossibility of quantum bit commitment
- Brassard, Crepeau, et al.
(Show Context)
Citation Context ...., Brassard 1988), a powerful primitive in cryptology, could be realized using quantum principles. However, Dominic Mayers (1996a and 1997) and Lo and Chau (1998) proved it to be impossible (see also =-=Brassard et al. 1997-=-). 10 Note that here the confidentiality is not guaranteed by the laws of physics, but relies on the assumption that Eve’s technology is limited, e.g. her antenna is finite, her detectors have limited... |

11 | Quantum cryptography with polarized photons in optical fibers, experiment and practical limits - Breguet, Muller, et al. - 1994 |

11 |
Quantum Repeaters: The Role of Imperfect
- Briegel, Dür, et al.
- 1998
(Show Context)
Citation Context ...that if in addition to the detectors’ noise there is noise due to decoherence, then the above idea can be extended, using entanglement purification. This is essentially the idea of quantum repeaters (=-=Briegel et al. 1998-=-, Dur et al. 1999). 21 IV. EXPERIMENTAL QUANTUM CRYPTOGRAPHY WITH FAINT LASER PULSES Experimental quantum key distribution was demonstrated for the first time in 1989 (it was published only in 1992 by... |

11 |
Quantum Cryptography on Noisy Channels: Quantum versus Classical Key-Agreement Protocols
- Gisin, Wolf
- 1999
(Show Context)
Citation Context ...see section VI E), then Alice and Bob can use advantage distillation if and only if Alice and Bob’s qubits are still entangled (they can thus use quantum privacy amplification (Deutsch et al. 1996)) (=-=Gisin and Wolf 1999-=-). This connection between the concept of entanglement, central to quantum information theory, and the concept of intrinsic classical information, central to classical information based cryptography (... |

11 |
Coherent eavesdropping strategies for the 4-state quantum cryptography protocol
- Cirac, Gisin
- 1997
(Show Context)
Citation Context ...correction and privacy amplification protocols originate from qubits attacked coherently. Consequently, the 15% bound would still be valid (partial results in favor of this conjecture can be found in =-=Cirac and Gisin 1997-=-, and in Bechmann-Pasquinuccisand Gisin 1999). However, if Eve has unlimited power, in particular, if she can coherently attack an unlimited number of qubits, then the 11% bound might be required. To ... |

10 |
W.P.: An autocompensating fiber-optic quantum cryptography system basedon polarization splitting of light
- Bethune, Risk
- 2000
(Show Context)
Citation Context ...8, Hiskett et al. 2000, Karlsson et al. 1999, and Rarity et al. 2000, Stucki et al. 2001), and first implementations for quantum cryptography have been reported (Ribordy 1998, Bourennane et al. 1999, =-=Bethune and Risk 2000-=-, Hughes et al. 2000b, Ribordy et al. 2000). However, if operating Ge APDs is already inconvenient compared to Silicon APDs, the handiness of InGaAs APDs is even worse, the problem being a extremely h... |

9 | Incoherent and coherent eavesdropping in the 6-state protocol of Quantum Cryptography, Phys
- Bechmann-Pasquinucci, Gisin
- 1999
(Show Context)
Citation Context ...es protocol in 1995. 2. 6-state protocol While two states are enough and four states are standard, a 6-state protocol respects much more the symmetry of the qubit state space, see Fig. 2 (Bruss 1998, =-=Bechmann-Pasquinucci and Gisin 1999-=-). The 6 states constitute 3 bases, hence the probability that Alice and Bob chose the same basis is only of 1 3 . But the symmetry of this protocol greatly simplifies the security analysis and reduce... |

8 |
Characterization of silicon avalanche photodiodes for photon correlation measurements. 2: Active quenching
- Brown, Jones, et al.
- 1987
(Show Context)
Citation Context ...charges stopped and the diode recharged (Cova et al. 1996). Three main possibilities exist: • In passive-quenching circuits, a large (50-500 kΩ) resistor is connected in series with the APD (see e.g. =-=Brown et al. 1986-=-). This causes a decrease of the voltage across the APD as soon as an avalanche starts. When it drops below breakdown voltage, the avalanche stops and the diode recharges. The recovery time of the dio... |

7 | Unambiguous state discrimination in quantum cryptography with weak coherent states - Duˇsek, Jahma, et al. |

7 |
Quantum cloning without signalling,” Phys
- Gisin
- 1998
(Show Context)
Citation Context ...qual to at most 5/6. Note that if it were possible to make better copies, then, using EPR correlations between spatially separated systems, signaling at arbitrarily fast speed would also be possible (=-=Gisin 1998-=-).sIII. TECHNOLOGICAL CHALLENGES The very first demonstration of QC was a table top experiment performed at the IBM laboratory in the early 1990’s over a distance of 30 cm (Bennett et al. 1992a), mark... |

6 | Operational system for quantum cryptography (Electronics Letters - Franson, Jacobs - 1995 |

5 |
Experiments on long wavelength (1550nm) ”plug and play” quantum cryptography systems
- Bourennane, Gibson, et al.
- 1999
(Show Context)
Citation Context ...1996, Ribordy et al. 1998, Hiskett et al. 2000, Karlsson et al. 1999, and Rarity et al. 2000, Stucki et al. 2001), and first implementations for quantum cryptography have been reported (Ribordy 1998, =-=Bourennane et al. 1999-=-, Bethune and Risk 2000, Hughes et al. 2000b, Ribordy et al. 2000). However, if operating Ge APDs is already inconvenient compared to Silicon APDs, the handiness of InGaAs APDs is even worse, the prob... |

4 | The Security of quantum bit commitment schemes
- Brassard, Mayers, et al.
- 1998
(Show Context)
Citation Context ...., Brassard 1988), a powerful primitive in cryptology, could be realized using quantum principles. However, Dominic Mayers (1996a and 1997) and Lo and Chau (1998) proved it to be impossible (see also =-=Brassard et al. 1998-=-). 11 Note that here the confidentiality is not guaranteed by the laws of physics, but relies on the assumption that Eve’s technology is limited, e.g. her antenna is finite, her detectors have limited... |

4 | Interferometer using a 3x3 coupler and Faraday - Breguet, Gisin - 1995 |

4 |
Experimental demonstration of optimal unambiguous state discrimination, Phys
- Clarke, Chefles, et al.
- 2001
(Show Context)
Citation Context ...usly without perturbation, one can unambiguously distinguish them at the cost of some losses (Ivanovic 1987, Peres 1988). This possibility has even been demonstrated in practice (Huttner et al. 1996, =-=Clarke et al. 2000-=-). Hence, Alice and Bob would have to monitor the attenuation of the 12 The idea is that Alice picks out several instances where she got the same bit and communicates the instances - but not the bit -... |

4 | Eavesdropping techniques in quantum cryptosystems - Ekert, Huttner - 1994 |

4 |
Experimental test of local hidden variable theories
- Fry, Thompson
- 1976
(Show Context)
Citation Context ... paradox (Einstein, Podolski and Rosen 1935): the initially philosophical debate turned to theoretical physics with Bell’s inequality (1964), then to experimental physics (Freedmann and Clauser 1972, =-=Fry and Thompson 1976-=-, and Aspect, Dalibard and Roger 1982), and is now – thanks to Ekert’s ingenious idea – part of applied physics. The idea consists in replacing the quantum channel carrying qubits from Alice to Bob by... |

4 | Bell inequality and the locality loophole: Active versus passive switches
- Gisin, Zbinden
- 1999
(Show Context)
Citation Context ...the locality loopholes, like the one performed in Innsbruck using fast polarization modulators (Weihs et al. 1998) or the one performed in Geneva using two analyzers on each side (Tittel et al. 1999; =-=Gisin and Zbinden 1999-=-). 43 Photon pair sources are often, though not always, pumped continuously. In these cases, the time window determined by a trigger detector and electronics defines an effective pulse.sThe coupling b... |

4 | Experimental long wavelength quantum cryptography: fromsimgle-photon transmission to key extraction protocols - Bourenane, Ljunggren, et al. - 2000 |

3 | Teleporting an Unknown Quantum State via Dual Classical and Einstein-Podolsky-Rosen Channels, Phys - Jozsa - 1993 |

3 |
Modern Cryptology, Springerverlag
- Brassard
- 1988
(Show Context)
Citation Context ...s valuable. Although confidentiality is the traditional application of cryptography, it is used nowadays to achieve broader objectives, such as authentication, digital signatures and non-repudiation (=-=Brassard 1988-=-). 1. Asymmetrical (public-key) cryptosystems Cryptosytems come in two main classes – depending on whether Alice and Bob use the same key. Asymmetricalssystems involve the use of different keys for en... |

3 |
Optimal universal quantum cloning and state
- Bruss, Ekert, et al.
- 1998
(Show Context)
Citation Context ...e � 2P↑↑ + P ψ (+) The corresponding fidelity is: F = 3 2 + 1 2 3 � = 5 6 = 2P↑ + 1 2 1 3 (21) (22) which is precisely the optimal fidelity compatible with quantum mechanics (Buˇzek and Hillery 1996, =-=Bruss et al 1998-=-, Gisin and Massar 1997). In other words, if we start with a single photon in an arbitrary state, and pass it through an amplifier, then due to the effect of spontaneous emission the fidelity of the s... |

3 |
personal communicatiOn
- Hadley
- 1975
(Show Context)
Citation Context ...ncrease of the information obtained by the eavesdropper. Moreover, they also recently implemented the six-state protocol described in paragraph II D2, and observed the predicted QBER increase to 33% (=-=Enzer et al. 2001-=-). The main advantage of polarization entanglement is the fact that analyzers are simple and efficient. It is therefore relatively easy to obtain high contrast. Naik and co-workers, for example, measu... |

3 |
Bell Inequality for Position and
- Franson
(Show Context)
Citation Context ... detection only on the central time peak, one observes two-photon interferences which depends on the sum of the relative phases 33 in Alice’s and Bob’s interferometer – non-local quantum correlation (=-=Franson 1989-=-) 45 – see Fig. 22. The phase in the interferometers at Alice’s and Bob’s can, for example, be adjusted so that both photons always emerge from the same output port. It is then possible to exchange bi... |

3 |
Nonlocal cancellation of dispersion, Phys
- Franson
- 1992
(Show Context)
Citation Context ... a temporal spread of around 500 ps (assuming photons centered at λ0 and a typical dispersion slope of 0.086 ps nm2km ). However, this can be compensated for when using energy-time entangled photons (=-=Franson 1992-=-, Steinberg et al. 1992a and 1992b, Larchuk et al. 1995). In contrast to polarization coding where frequency and the physical property used to implement the qubit are not conjugate variables, frequenc... |

3 | Efficient quantum key distribution,’’ preprint quant-ph/9803007 - Ardehali, Chau, et al. - 1998 |

2 |
High accuracy picosecond characterization of gain-switched laser diodes
- Cova, Lacaita, et al.
- 1989
(Show Context)
Citation Context ...ultipliers used until then in the domain of fundamental quantum optics, known now as quantum communication. Today, quantum efficiencies of up to 76% (Kwiat et al. 1993) and time jitter down to 28 ps (=-=Cova et al. 1989-=-) have been reported. Commercial single photon counting modules are available (EG&G SPCM-AQ-151), featuring quantum efficiencies of 70 % at a wavelength of 700 nm, a time jitter of around 300 psec and... |

2 | Shrödinger cat states and optimum universal quantum cloning by entangled parametric amplification - Martini, Mussi, et al. - 2000 |

2 |
The golden age of optical fiber amplifiers. Phys. Today, January issue
- Desurvire
- 1994
(Show Context)
Citation Context ...t these “ideal measurements” do not invalidate the security of QC. Let us consider now optical amplifiers (a laser medium, but without mirrors, so that amplification takes place in a single pass, see =-=Desurvire 1994-=-). They are widely used in today’s optical communication networks. However, they are of no use for quantum communication. Indeed, as seen in section II C, the copying of quantum information is impossi... |

1 | and Mermin N.D., 1992b, “Quantum cryptography without Bell’s theorem - Bennett, Brassard |

1 |
Security of quantum cryptograophy against collective attacks
- Biham, Mor
- 1997
(Show Context)
Citation Context ...ob are isolated from Eve. C. Individual, joint and collective attacks In order to simplify the problem, several eavesdropping strategies of restricted generalities have been defined (Lütkenhaus 1996, =-=Biham and Mor 1997-=-a and 1997b) and analyzed. Of particular interest is the assumption that Eve attaches independent probes to each qubit and measures her probes one after the other. This class of attacks is called indi... |

1 | Experimental long wavelength quantum cryptography: from single photon transmission to key extraction protocols - Hening, Ciscar - 2000 |

1 | Geometric phase in 2-photon interference experiments”, Phys. rev - Brendel, Dultz, et al. - 1995 |

1 | Triggered Source of Single Photons based on Controlled Single Molecule Fluorescence - Tamarat, Orrit - 1999 |

1 |
Single-mode optical fiber measurement: characterization and sensing”, Artech House
- Cancellieri
- 1993
(Show Context)
Citation Context ... in a stable relation with the phase at the input, provided the fiber doesn’t get elongated. Hence, fiber interferometers are very stable, a fact exploited in many instruments and sensors (see, e.g., =-=Cancellieri 1993-=-). Accordingly, a singlemode fiber with perfect cylindric symmetry would provide an ideal quantum channel. But all real fibers have some asymmetries and then the two polarization modes are no longer d... |

1 | Complex mode coupling within air-silica structured optical fibers and applications - Canning, Eijkelenborg, et al. - 2000 |

1 | Quantum privacy amplification and the security of quantum cryptography over noisy channels - Popescu, Sanpera - 1996 |

1 | Coded secrets cracked open - Ekert - 2000 |

1 | Statistical prediction and experimental verification of concatenations of fibre optic components with polarization dependent loss - Zimmer - 1998 |

1 | Enhanced Spontaneous Emission by Quantum Boxes in a Monolithic Optical Microcavity”, Phys - Costard, Thierry-Mieg - 1998 |

1 | Strong Purcell Effect for InAs Qantum Boxes in Three-Dimensional Solid-State - Gérard, Gayral - 1999 |

1 |
Definition of Polarization Mode Dispersion and First
- Gisin
- 1995
(Show Context)
Citation Context ...d it the nickname of “plug & play” set-up. It is interesting to note that the idea of combining time-multiplexing with Faraday mirrors was first used to implement an “optical microphone” (Bréguet and =-=Gisin, 1995-=-) 38 . However, our first realization still suffered from certain optical inefficiencies, and has been improved since then. Similar to the setup tested in 1997, the new system is based on time multipl... |

1 | A proof of the securiity of quantum key distribution - Biham, Boyer, et al. - 1999 |

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1 | A proof of the security of quantum key distribution,’’ preprint quant-ph/9912053 - Biham, Boyer, et al. - 1999 |

1 | A proof of the security of quantum key distribution - E, Boykin, et al. - 1999 |