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1.
The security of quantum secret sharing based on entanglement
swapping is revisited and a participant attack is presented. In this
attack two dishonest agents together can illegally recover the
secret quantum state without the help of any other controller, and
it will not be detected by any other users. Furthermore, by
modifying the distribution process of particles and adding a
detection step after each distribution process, we propose an
improved protocol which can resist this kind of attack. 相似文献
2.
This paper proposes a scheme for teleporting a kind of essential three-particle
non-symmetric entangled state, which is much more valuable than a GHZ and W state
for some applications in quantum information processing. In comparison with previous
proposal of teleportation, the resources of entangled states as quantum channel and
the number of classical messages required by our scheme can be cut down. Moreover,
it is shown that there exists a class of transformations which ensure the success of
this scheme, because the two-particle transformation performed by the receiver in
the course of teleportation may be a generic two-particle operation instead of a
control-NOT (CNOT) operation. In addition, all kinds of transformations performed by
sender and receiver are given in detail. 相似文献
3.
Improvement of total-dose irradiation hardness of silicon-on-insulator materials by modifying the buried oxide layer with ion implantation 下载免费PDF全文
The hardening of the buried oxide (BOX) layer of separation by implanted
oxygen (SIMOX) silicon-on-insulator (SOI) wafers against total-dose irradiation
was investigated by implanting ions into the BOX layers. The tolerance to
total-dose irradiation of the BOX layers was characterized by the
comparison of the transfer
characteristics of SOI NMOS transistors before and after irradiation to
a total dose of 2.7
Mrad(SiO2. The experimental results show that the implantation of
silicon ions into the BOX layer can improve the tolerance of the BOX layers
to total-dose irradiation. The investigation of the mechanism of the
improvement suggests that the deep electron traps introduced by silicon
implantation play an important role in the remarkable improvement in
radiation hardness of SIMOX SOI wafers. 相似文献
4.
In this paper, we use our method to solve the extended Lotka--Volterra equation and
discrete KdV equation. With the help of Maple, we obtain a number of exact solutions
to the two equations including soliton solutions presented by hyperbolic functions
of \sinh and \cosh, periodic solutions presented by trigonometric functions of
\sin and \cos, and rational solutions. This method can be used to solve some
other nonlinear difference--differential equations. 相似文献
5.
Generally the incompressible viscous flow problem is described by the Navier--Stokes
equation. Based on the weighted residual method the discrete formulation of
element-free Galerkin is inferred in this paper. By the step-by-step computation in
the field of time,
and adopting the least-square estimation of the-same-order shift,
this paper has calculated
both velocity and pressure
from the decoupling independent equations.
Each time fraction Newton--Raphson iterative method is applied for
the velocity and pressure. Finally, this paper puts the method into
practice of the shear-drive cavity flow, verifying the validity,
high accuracy and stability. 相似文献
6.
A theory of excitation of ultrasonic waves in the stimulated Brillouin
scattering (SBS) process is presented in this paper. By using several
reasonable approximations, a numerical calculation of the transient
longitudinal SBS shows that large amplitude of acoustic waves can be built
up by the nanosecond pulse of high-power laser, which may result in the
damage of optical glasses. The maximal density change and the maximal
acoustic wave intensity in optical glasses of 5\,cm in thickness are
calculated by using different parameters of the high-energy laser, such as
the intensity, the pulse width, and the wave length. The damage threshold of
the optical glasses is about 80 GW/cm^{2} when using a 1064 nm laser. The
dynamic mechanism of SBS is the electrostriction effect of the components
coupling with the high-power laser. 相似文献
7.
Semi-quantitative study on the Staebler--Wronski effect of hydrogenated amorphous silicon films prepared with HW-ECR-CVD system 总被引:1,自引:0,他引:1 下载免费PDF全文
The method of numerical simulation is used to fit the relationship between
the photoconductivity in films and the illumination time. The generation and
process rule of kinds of different charged defect states during illumination
are revealed. It is found surprisingly that the initial photoconductivity
determines directly the total account of photoconductivity degradation of
sample. 相似文献
8.
Hawking radiation as tunnelling from arbitrarily dimensional Reissner-Nordstrom de Sitter black hole 下载免费PDF全文
This paper extends Parikh-Wilzcek's recent work, which treats the Hawking radiation as a semi-classical tunnelling process from the event horizon of four dimensional Schwarzshild and Reissner-Nordstrom black holes, to that of arbitrarily dimensional Reissner-Nordstrom de Sitter black hole. The result shows that the tunnelling rate is related to the change of Bekenstein-Hawking entropy and the factually radiant spectrum is no longer precisely thermal after taking the dynamical black hole background and energy conservation into account, but is consistent with the underlying unitary theory and then satisfies the first law of the black hole thermodynamics. Meanwhile, in Parikh-Wilzcek's framework, this paper points out that the information conservation is only suitable for the reversible process but in highly unstable evaporating black hole (irreversible process) the information loss is possible. 相似文献
9.
Remote preparation of a Greenberger--Horne--Zeilinger state via a two-particle entangled state 总被引:2,自引:0,他引:2 下载免费PDF全文
We present two schemes for realizing the remote preparation of a
Greenberger--Horne--Zeilinger (GHZ) state. The first scheme is to remotely
prepare a general N-particle GHZ state with two steps. One is to prepare a qubit
state by using finite classical bits from sender to receiver via a
two-particle entangled state, and the other is that the receiver introduces
N - 1 additional particles and performs N - 1 controlled-not (C-Not)
operations. The second scheme is to remotely prepare an N-atom
GHZ state via
a two-atom entangled state in cavity quantum electrodynamics (QED). The two
schemes require only a two-particle entangled state used as a quantum
channel, so we reduce the requirement for entanglement. 相似文献
10.
We investigate schemes for quantum secret sharing and quantum dense
coding via tripartite entangled states. We present a scheme for
sharing classical information via entanglement swapping using two
tripartite entangled GHZ states. In order to throw light upon the
security affairs of the quantum dense coding protocol, we also
suggest a secure quantum dense coding scheme via W state by
analogy with the theory of sharing information among involved users. 相似文献
11.
XIA Yan SONG Jie SONG He-Shan HUANG Xiao-Li HUANG Xiao-Li 《理论物理通讯》2008,49(6):1468-1472
We propose a new multiparty quantum secret sharing protocol via introducing auxiliary particles using a non-maximally entangled (pure) two-particle state without a Bell measurement. The communication parties utilize decoy particles tO check eavesdropping. After ensuring the security of the quantum channel, the sender encodes the secret message and transmits it to the receiver by using controlled-NOT operation and von Neumann measurement. If and only if all the agents agree to collaborate, they can read out the secret message. 相似文献
12.
A scheme for teleporting an unknown N-particle entangled W state is proposed via entanglement swapping. In this scheme, N maximally entangled particle pairs are used as quantum channel. As a special case, the teleportation of an unknown four-particle entangled W state is studied. 相似文献
13.
Controlled quantum state sharing of arbitrary two-qubit states with five-qubit cluster states 下载免费PDF全文
In this paper, we propose a controlled quantum state sharing scheme to share an arbitrary two-qubit state using a five-qubit cluster state and the Bell state measurement. In this scheme, the five-qubit cluster state is shared by a sender (Alice), a controller (Charlie), and a receiver (Bob), and the sender only needs to perform the Bell-state measurements on her particles during the quantum state sharing process, the controller performs a single-qubit projective measurement on his particles, then the receiver can reconstruct the arbitrary two-qubit state by performing some appropriate unitary transformations on his particles after he has known the measured results of the sender and the controller. 相似文献
14.
By using the solutions of an auxiliary Lam\'e equation, a direct algebraic method is
proposed to construct the exact solutions of $N$-coupled nonlinear Schr\"{o}dinger
equations. The abundant higher-order exact periodic solutions of a family of
$N$-coupled nonlinear Schr\"{o}dinger equations are explicitly obtained with the aid
of symbolic computation and they include corresponding envelope solitary and shock
wave solutions. 相似文献
15.
Nanosecond-time-resolved infrared spectroscopic study of fast relaxation kinetics of protein folding by means of laser-induced temperature-jump 下载免费PDF全文
Elucidating the initial kinetics of folding pathways is critical to the understanding of the protein folding mechanism. Transient infrared spectroscopy has proved a powerful tool to probe the folding kinetics. Herein we report the construction of a nanosecond laser-induced temperature-jump (T-jump) technique coupled to a nanosecond timeresolved transient mid-infrared (mid-IR) spectrometer system capable of investigating the protein folding kinetics with a temporal resolution of 50 ns after deconvolution of the instrumental response function. The mid-IR source is a liquid N2 cooled CO laser covering a spectral range of 5.0μm (2000 cm^-1)-6.5μm (1540 cm^-1). The heating pulse was generated by a high pressure H2 Raman shifter at wavelength of 1.9μm. The maximum temperature-jump could reach as high as 26±1℃. The fast folding/unfolding dynamics of cytochrome C was investigated by the constructed system, providing an example. 相似文献
16.
Proof of the insecurity of quantum secret sharing based on the Smolin bound entangled states 下载免费PDF全文
This paper reconsiders carefully the possibility of using the
Smolin bound entangled states as the carrier for sharing quantum
secret. It finds that the process of quantum secret sharing based on
Smolin states has insecurity though the Smolin state was reported to
violate maximally the two-setting Bell-inequality. The general proof
is given. 相似文献
17.
Transfer of entangled state, entanglement swapping and quantum information processing via the Rydberg blockade 下载免费PDF全文
We provide a scheme with which the transfer of the entangled state and the entanglement swapping can be realized in a system of neutral atoms via the Rydberg blockade. Our idea can be extended to teleport an unknown atomic state. According to the latest theoretical research of the Rydberg excitation and experimental reports of the Rydberg blockade effect in quantum information processing, we discuss the experimental feasibility of our scheme. 相似文献
18.
This paper proposes a protocol for multi-party quantum secret sharing utilizing four non-orthogonal two-particle entangled states following some ideas in the schemes proposed by Liu et al. (2006 Chin. Phys. Lett. 23 3148) and Zhang et al. (2009 Chin. Phys. B 18 2149) respectively. The theoretical efficiency for qubits of the new protocol is improved from 50% to approaching 100%. All the entangled states can be used for generating the private key except those used for the eavesdropping check. The validity of a probable attack called opaque cheat attack to this kind of protocols is considered in the paper for the first time. 相似文献
19.
Cryptanalysis and improvement of a quantum secret sharing scheme based on x-type entangled states 下载免费PDF全文
In the paper [2010 Chin. Phys. B 19 050306], Yang et al. put forward a novel three-party quantum secret sharing protocol of secure direct communication based on χ-type entangled states, they claimed that the scheme is secure. However, in this paper, we study the security of the protocol and find that it is insecure. Applying intercept and resend attack, the agent Bob can obtain Alice’s secret without the help from the other agent Charlie. In the end, we give our effective modification for its improvement. 相似文献
20.
It is generally believed that nonorthogonal operations which can
realize the state transformation between two nonorthogonal bases may
ensure the security of many quantum communication protocols.
However, in this paper, we present a powerful attack against quantum
secret sharing protocols of these kinds. Applying entangled photons
as fake signals, Eve can successfully steal the exact information
without being revealed. We also give our effective modification to
improve it. Under the suggested checking strategy, even to Eve's
most general attack, it is robust and secure. 相似文献