[Show abstract][Hide abstract] ABSTRACT: By exploiting the hyperentanglement, we propose a new concrete scheme to
realize weak value amplification, which can be implemented by N hyperentangled
photons along with coincidence detection. Our scheme can optimally increase the
amplification factor by a factor of N compared to the usage of N uncorrelated
photons, and achieve the Heisenberg limit for the purpose of parameter
estimation. We expect our study can inspire a further investigation on the
usage of hyperentanglement in weak measurement and quantum metrology.
[Show abstract][Hide abstract] ABSTRACT: In the quantum metrology, applications of quantum techniques based on
entanglement bring in some better performances than conventional
approaches. We experimentally investigate an application of entanglement
in accurate ranging based on the second-order coherence in the time
domain. By a fitting algorithm in the data processing, the optimization
results show a precision of ±200 μm at a distance of 1043.3m.
In addition, the influence of jamming noise on the ranging scheme is
studied. With some different fitting parameters, the result shows that
the proposed scheme has a powerful anti-jamming capability for white
Chinese Physics Letters 10/2013; 30(10):0301-. DOI:10.1088/0256-307X/30/10/100301 · 0.95 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Coherent source of continuous-variable quantum key distribution (CV QKD) system may become noisy in practical applications. The security of CV-QKD scheme with the noisy coherent source is investigated under realistic conditions of quantum channel and detector. In particular, two models are proposed to characterize the noisy coherent source through introducing a party (Fred) who induces the noise with an optical amplifier. When supposing the party Fred is untrusted, two lower security bounds to the noise of the coherent source are derived for reverse reconciliation and realistic homodyne and heterodyne detections. While supposing Fred is a neutral party, we derive two tight security bounds without knowing Fred’s exact state for ideal detections. Moreover, the simulation results show that the security of the reverse reconciliation CV-QKD protocols is very sensitive to the noise of coherent source for both the homodyne and heterodyne detections.
International Journal of Theoretical Physics 05/2013; 52(5). DOI:10.1007/s10773-012-1475-1 · 1.19 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The dynamics of classical and quantum correlations under nondissipative and dissipative decoherences are analytically and numerically investigated with both one-side measures and two-side measures. Specifically, two qubits under local amplitude damping decoherence and depolarizing decoherence channels are considered. We show that, under the action of amplitude damping decoherence, both the entanglement and correlations of the different types of initial states with same initial values, suffer different types of dynamics. Moreover, the transfers of the entanglement and correlations between the system and the environment for different types of initial states are also shown to be different. While for the action of depolarizing decoherence, there does not exist sudden change in the decay rates of both the classical and quantum correlations, which is different from some other nondissipative channels. Furthermore, the quantum dissonance can be found to keep unchanged under the action of depolarizing decoherence. Such different dynamic behaviors of different noisy quantum decoherence channels reveal distinct transmission performance of classical and quantum information.
Quantum Information Processing 12/2012; 11(6). DOI:10.1007/s11128-011-0335-x · 2.96 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Two continuous-variable quantum identity authentication schemes, which are utilized to prevent active attack, are presented by using Gaussian-modulated squeezed states. The proposed schemes can both verify user’s identity as well as distribute an updated new key as the authentication key. A new defined fidelity parameter is proposed to verify the identity of the communicator and detect eavesdropping. The analytical results show the feasibility of these two identity authentication schemes and the security under the attack of general Gaussian-cloner strategy and collective attack.
International Journal of Quantum Information 03/2011; 9(2). DOI:10.1142/S0219749911007745 · 0.99 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The security, efficiency, transmission distance and error rate are important parameters of a quantum key distribution scheme. In this article, the former two parameters are focused on. To reach high efficiency, an unsymmetrical quantum key distribution scheme that employs Greenberger-Horne-Zeilinger (GHZ) triplet states and dense coding mechanism is proposed, in which a GHZ triplet state can be used to share two bits of classical information. The proposed scheme can be employed in a noisy or lossy quantum channel. In addition, a general approach to security analysis against general individual attacks is presented.
The Journal of China Universities of Posts and Telecommunications 06/2009; 16(3-16):114-121. DOI:10.1016/S1005-8885(08)60236-8
[Show abstract][Hide abstract] ABSTRACT: Security of wireless sensor network (WSN) is a considerable challenge, because of limitation in energy, communication bandwidth
and storage. ID-based cryptosystem without checking and storing certificate is a suitable way used in WSN. But key escrow
is an inherent disadvantage for traditional ID-based cryptosystem, i.e., the dishonest key generation center (KGC) can forge
the signature of any node and on the other hand the node can deny the signature actually signed by him/herself. To solving
this problem, we propose an ID-based ring signature scheme without trusted KGC. We also present the accurate secure proof
to prove that our scheme is secure against existential forgery on adaptively chosen message and ID attacks assuming the complexity
of computational Diffie-Hellman (CDH) problem. Compared with other ring signature schemes, we think proposed scheme is more
Journal of Shanghai Jiaotong University (Science) 04/2009; 14(2):189-194. DOI:10.1007/s12204-009-0189-x
[Show abstract][Hide abstract] ABSTRACT: A quantum secure direct intercommunication scheme is proposed to exchange directly the communicators' secret messages by making use of swapping entanglement of Bell states. It has great capacity to distribute the secret messages since these messages have been imposed on high-dimensional Bell states via the local unitary operations with superdense coding. The security is ensured by the secure transmission of the travel sequences and the application of entanglement swapping.