Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Eavesdropping using quantum-nondemolition measurements

M. J. Werner, Gerard J Milburn

Published Jan 1, 1993• 7 citations
Publisher

Abstract

We investigate the effects of photon-number quantum-nondemolition measurements performed by an eavesdropper on a two-photon correlated state. The relation between this model and quantum cryptography is discussed. It is shown that violation of Bell's inequality is very sensitive to the probe amplitude of the measurement system.
DOI
10.1103/physreva.47.639

Related papers

Entangled State Quantum Cryptography: Eavesdropping on the Ekert Protocol

D. Naik, Charles G. Peterson, Andrew G. White +2 more

Using polarization-entangled photons from spontaneous parametric down-conversion, we have implemented Ekert's quantum cryptography protocol. The near-perfect correlations of the photons allow the sharing of a secret key between two parties. The presence of an eavesdropper is continually checked by measuring Bell's inequalities. We investigated several possible eavesdropper strategies, including pseudo-quantum-nondemolition measurements. In all cases, the eavesdropper's presence was readily apparent. We discuss a procedure to increase her detectability.

arXiv:quant-ph/9912105•Physical Review Letters•May 15, 2000•390 citations

Quantum cloning, eavesdropping and Bell’s inequality [Physics Letters A 228

Nicolas Gisin, B. Hüttner

We analyze various eavesdropping strategies on a quantum cryptographic channel. We present the optimal strategy for an eavesdropper restricted to a two-dimensional probe, interacting on-line with each transmitted signal. The link between safety of the transmission and the violation of Bell’s inequality is discussed. We also use a quantum copying machine for eavesdropping and for broadcasting quantum information. 1

•Jan 1, 1997•4 citations

Quantum communication and security

Yi Mu

This dissertation is composed of the results of our investigation in quantum cryptography - a new topic in computer security. The goal of this study is to explore useful schemes for quantum cryptographic communications. The focus of our study is an investigation into quantum cryptographic protocols based on quantum-mechanical uncertainty principle and Bell's inequality. First, we use the theory of quadrature phase amplitudes and quantum homodyne detection to establish a new quantum key distribution protocol which relies on an optical coupler. In this work we propose, for the first time, the use of this theory in quantum cryptography. Second, we investigate Ekert's protocol using Bell's theorem. The contents in this investigation is not new, but we use our calculation to prove that Ekert's protocol is true for both photon-based and spin- |-particle-bcised systems. Third, we study a quantum coherence key distribution constructed using Bennett and Brassard's protocol. The information theory of the system is used to study the scenario where eavesdropping occurs. Finally, we explore the theory of quantum nondemolition detection (QND) to investigate the results when eavesdropping occurs. A calculation for the QND, using parametric frequency conversion, is given for two different quantum cryptographic systems. Our study is undertaken with the aid of some knowledge of physics, therefore, before our main results are presented, we introduce some useful physics which may help readers understand the contents of our work.

•Jan 1, 1994•5 citations

Entangled-photon quantum cryptography

Paul G. Kwiat, Andrew G. White, Charles G. Peterson +1 more

Summary form only given. Quantum cryptography uses single photons to allow secure distribution of secret key material to sender and receiver, without the possibility of an undetected eavesdropper. In the protocol suggested by Ekert, each photon of a quantum-mechanically entangled pair is sent to the sender and receiver, who randomly measure the polarization in various bases. If the bases are the same, then sender and receiver will have completely correlated measurement results, which become the shared secret key. Other combinations of measurements are used to test Bell's inequalities, which limit the possible correlations achievable with any local realistic theory. The presence of an intermediate eavesdropper can be readily detected by an inability to violate Bell's inequality. Using the polarization-entangled photon pairs from a novel spontaneous parametric down-conversion source, we have experimentally implemented. Ekert's proposal.

Quantum Electronics and Laser Science Conference•May 12, 2000•0 citations

Security proof for quantum cryptography against entanglement-measurement attack

Zhaoxu Ji, Huanguo Zhang

Entanglement-measurement attack is one of the most famous attacks against quantum cryptography. In quantum cryptography protocols, eavesdropping checking is an effective means to resist this attack. There are currently two commonly used eavesdropping checking methods: one is to prepare two sets of non-orthogonal single-particle states as decoy states, and determine whether there are eavesdroppers in the quantum channel by comparing the states obtained by measurements with the original states; The other is to prepare two sets of non-orthogonal entangled states and use their entanglement correlations to judge whether there are eavesdroppers in the quantum channel. In this paper, we theoretically demonstrate how quantum cryptography can utilize these two eavesdropping checking methods to resist entanglement-measurement attacks. We take the quantum cryptography protocols based on maximally entangled states as examples to demonstrate the proof process, transitioning from qubit-based protocols to qudit-based ones.

arXiv:2012.14275•Dec 24, 2020•4 citations

Quantum nondemolition measurement of the photon number via the optical Kerr effect

N. Imoto, H. A. Haus, Y. Yamamoto

This paper proposes a quantum nondemolition measurement scheme for the photon number. The signal and probe optical waves interact via the optical Kerr effect. The optical phase of the probe wave is selected as the readout observable for the measurement of the photon number of the signal wave. The measurement accuracy \ensuremath{\Delta}n and the imposed phase noise \ensuremath{\Delta}\ensuremath{\varphi} of the signal wave satisfy Heisenberg's uncertainty principle with an equality sign, 〈(\ensuremath{\Delta}n${)}^{2}$〉〈(\ensuremath{\Delta}\ensuremath{\varphi}${)}^{2}$〉=(1/4). .AE

Physical Review A•Oct 1, 1985•605 citations
Using polarization-entangled photons from spontaneous parametric down-conversion, we have implemented Ekert's quantum cryptography protocol. The near-perfect correlations of the photons allow the sharing of a secret key between two parties. The presence of an eavesdropper is continually checked by measuring Bell's inequalities. We investigated several possible eavesdropper strategies, including pseudo-quantum-nondemolition measurements. In all cases, the eavesdropper's presence was readily apparent. We discuss a procedure to increase her detectability.
This dissertation is composed of the results of our investigation in quantum cryptography - a new topic in computer security. The goal of this study is to explore useful schemes for quantum cryptographic communications. The focus of our study is an investigation into quantum cryptographic protocols based on quantum-mechanical uncertainty principle and Bell's inequality. First, we use the theory of quadrature phase amplitudes and quantum homodyne detection to establish a new quantum key distribution protocol which relies on an optical coupler. In this work we propose, for the first time, the use of this theory in quantum cryptography. Second, we investigate Ekert's protocol using Bell's theorem. The contents in this investigation is not new, but we use our calculation to prove that Ekert's protocol is true for both photon-based and spin- |-particle-bcised systems. Third, we study a quantum coherence key distribution constructed using Bennett and Brassard's protocol. The information theory of the system is used to study the scenario where eavesdropping occurs. Finally, we explore the theory of quantum nondemolition detection (QND) to investigate the results when eavesdropping occurs. A calculation for the QND, using parametric frequency conversion, is given for two different quantum cryptographic systems. Our study is undertaken with the aid of some knowledge of physics, therefore, before our main results are presented, we introduce some useful physics which may help readers understand the contents of our work.
Summary form only given. Quantum cryptography uses single photons to allow secure distribution of secret key material to sender and receiver, without the possibility of an undetected eavesdropper. In the protocol suggested by Ekert, each photon of a quantum-mechanically entangled pair is sent to the sender and receiver, who randomly measure the polarization in various bases. If the bases are the same, then sender and receiver will have completely correlated measurement results, which become the shared secret key. Other combinations of measurements are used to test Bell's inequalities, which limit the possible correlations achievable with any local realistic theory. The presence of an intermediate eavesdropper can be readily detected by an inability to violate Bell's inequality. Using the polarization-entangled photon pairs from a novel spontaneous parametric down-conversion source, we have experimentally implemented. Ekert's proposal.
Entanglement-measurement attack is one of the most famous attacks against quantum cryptography. In quantum cryptography protocols, eavesdropping checking is an effective means to resist this attack. There are currently two commonly used eavesdropping checking methods: one is to prepare two sets of non-orthogonal single-particle states as decoy states, and determine whether there are eavesdroppers in the quantum channel by comparing the states obtained by measurements with the original states; The other is to prepare two sets of non-orthogonal entangled states and use their entanglement correlations to judge whether there are eavesdroppers in the quantum channel. In this paper, we theoretically demonstrate how quantum cryptography can utilize these two eavesdropping checking methods to resist entanglement-measurement attacks. We take the quantum cryptography protocols based on maximally entangled states as examples to demonstrate the proof process, transitioning from qubit-based protocols to qudit-based ones.
This paper proposes a quantum nondemolition measurement scheme for the photon number. The signal and probe optical waves interact via the optical Kerr effect. The optical phase of the probe wave is selected as the readout observable for the measurement of the photon number of the signal wave. The measurement accuracy \ensuremath{\Delta}n and the imposed phase noise \ensuremath{\Delta}\ensuremath{\varphi} of the signal wave satisfy Heisenberg's uncertainty principle with an equality sign, 〈(\ensuremath{\Delta}n)2{)}^{2})2〉〈(\ensuremath{\Delta}\ensuremath{\varphi})2{)}^{2})2〉=(1/4). .AE