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1.
In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization,
a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem.
Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without
a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum
threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t − 1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t − 1 or fewer receivers cannot verify the validity of the signature.
Supported by the National Basic Research Program of China (973 Program)(Grant No. 2007CB311100), the National High-Technology
Research and Development Program of China (Grant Nos. 2006AA01Z419 and 2006AA01Z440), the Major Research Plan of the National
Natural Science Foundation of China (Grant No. 90604023), the Scientific Research Common Program of Beijing Municipal Commission
of Education (Grant No. KM200810005004), the Scientific Research Foundation for the Youth of Beijing University of Technology
(Grant No. 97007016200701), the Doctoral Scientific Research Activation Foundation of Beijing University of Technology (Grant
No. 52007016200702), the ISN Open Foundation, and the National Laboratory for Modern Communications Science Foundation of
China (Grant No. 9140C1101010601) 相似文献
2.
For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology. 相似文献
3.
Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the
users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol, the TTP shares a random key
K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA, the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share, each user performs the corresponding unitary operations on the single photon sequence
sequentially. At last, the TTP can judge whether the impersonator exists. The second protocol is a modified version with a
circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technology.
Supported by the National Basic Research Program of China (973 Program) (Grant No. 2007CB311100), the National High Technology
Research and Development Program of China (Grant Nos. 2006AA01Z419 and 20060101Z4015), the Major Research Plan of the National
Natural Science Foundation of China (Grant No. 90604023), the Scientific Research Common Program of Beijing Municipal Commission
of Education (Grant No. KM200810005004), the Scientific Research Foundation for the Youth of Beijing University of Technology
(Grant No. 97007016200701), the National Research Foundation for the Doctoral Program of Higher Education of China (Grant
No. 20040013007), the National Laboratory for Modern Communications Science Foundation of China (Grant No. 9140C1101010601),
and the Doctor Scientific Research Activation Foundation of Beijing University of Technology (Grant No. 52007016200702) 相似文献
4.
A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single
photons, which is useful and efficient when the parties of communication are not all present. We described the process of
this TQSS scheme and discussed its security. It was shown that entanglement is not necessary for quantum secret sharing. Moreover,
the theoretic efficiency was improved to approach 100% as almost all the instances can be used for generating the private
key, and each photon can carry one bit of information. This protocol is feasible with the present-day technique.
Supported by the National Basic Research Program of China (973 Program)(Grant No. 2007CB311100), the National High-Technology
Research and Development Program of China (Grant Nos. 2006AA01Z419 and 2006AA01Z440), the Major Research Plan of the National
Natural Science Foundation of China (Grant No. 90604023), the Scientific Research Common Program of Beijing Municipal Commission
of Education (Grant No. KM200810005004), the Scientific Research Foundation for the Youth of Beijing University of Technology
(Grant No. 97007016200701), the Doctoral Scientific Research Activation Foundation of Beijing University of Technology (Grant
No. 52007016200702), the ISN Open Foundation, and the National Laboratory for Modern Communications Science Foundation of
China (Grant No. 9140C1101010601) 相似文献
5.
From the perspective of information theory and cryptography, the security of two quantum dialogue protocols and a bidirectional
quantum secure direct communication (QSDC) protocol was analyzed, and it was pointed out that the transmitted information
would be partly leaked out in them. That is, any eavesdropper can elicit some information about the secrets from the public
annunciations of the legal users. This phenomenon should have been strictly forbidden in a quantum secure communication. In
fact, this problem exists in quite a few recent proposals and, therefore, it deserves more research attention in the following
related study.
Supported by the National High Technology Research and Development Program of China (Grant No. 2006AA01Z419), the National
Natural Science Foundation of China (Grant Nos. 90604023 and 60373059), the National Research Foundation for the Doctoral
Program of Higher Education of China (Grant No. 20040013007), the National Laboratory for Modern Communications Science Foundation
of China (Grant No. 9140C1101010601), the Natural Science Foundation of Beijing (Grant No. 4072020) and the ISN Open Foundation 相似文献
6.
The way to compare the efficiencies of different detect strategies (DSs) in the “ping-pong” protocol is studied. The trade-off
between information gain and disturbance is calculated and compared for different DSs. The comparison result primely tallies
with our intuitional analysis. It is shown that the analysis of this trade-off is a feasible way to compare the performances
of different DSs in theory.
Supported by the National High Technology Research and Development Program of China (Grant No. 2006AA01Z419), the National
Natural Science Foundation of China (Grant Nos. 90604023 and 6087319), the National Laboratory for Modern Communications Science
Foundation of China (Grant No. 9140C1101010601), the Natural Science Foundation of Beijing (Grant No. 4072020), and the ISN
Open Foundation. 相似文献
7.
Recently, Yang et al. proposed a kind of quantum cryptographic schemes based on secret sharing. The main idea is drawn from the case, where any n participants who share a secret K can co-operate as K does. This process can be applied to encryption, authentication, signature and so on. Unfortunately, since there is no identity authentication of the share’s holder, these schemes inherit the limitation of secret sharing in practice. If some participants do not follow the protocol, the protocol would be a failu... 相似文献
8.
A multi-proxy quantum group signature scheme with threshold shared verification is proposed. An original signer may authorize a proxy group as his proxy agent. Then only the cooperation of all the signers in the proxy group can generate the proxy signature on behalf of the original signer. In the scheme, any t or more of n receivers can verify the message and any t - 1 or fewer receivers cannot verify the validity of the proxy signature. 相似文献
9.
The electronic structure of stressed CrSi2 was calculated using the first-principle methods based on plane-wave pseudo-potential theory. The calculated results showed
that, under the uniaxial compression, the energy level of CrSi2 shifted toward high energy and its energy gap became wider with the increasing uniaxial stress, while the gap became narrower
under the negative uniaxial stress. When the negative uniaxial stress was up to −18.5 GPa, CrSi2 was converted into a direct-gap semiconductor with the band gap of 0.32 eV.
Supported by the National Natural Science Foundation of China (Grant No. 60566001), the Specialized Research Fund for the
Doctoral Program of Higher Education of China (Grant No. 20050657003), the Scientific Research Foundation for the Returned
Overseas Chinese Scholars, Ministry of Education of China (Grant No. (2005)383), the Program for the Excellent Young Talents
of Guizhou Province (Grant No. 20050528), the Specialized Nomarch Research Fund for the Excellent Science and Technology and
Education Talent’s Projects of Guizhou Province, Scientific and Technological Projects for the Returned Overseas Chinese Scholars,
the Guizhou Province (Grant No. (2004)03), and the Top Talent’s Scientific Research Project of Organization Department of
Guizhou Province 相似文献
10.
Using the first principle methods based on the plane-wave pseudo-potential theory, band structure, density of states and optical
properties of CrSi2 were studied. The calculation of band structure shows that CrSi2 is an indirect semiconductor whose band gap is 0.353 eV. Density of states is mainly composed of 3d electron of Cr and 3p
electron of Si. Dielectric function, refractive index, reflectivity, and absorption coefficient of CrSi2 are also calculated. The calculation results of optical properties are in agreement with the experiments.
Supported by the National Natural Science Foundation of China (Grant No. 60566001), the Specialized Research Fund for the
Doctoral Program of Higher Education of China (Grant No. 20050657003), the Scientific Research Foundation for the Returned
Overseas Chinese Scholars, Ministry of Education of China (Grant No. (2005)383), the Program for Excellent Young Talents of
Guizhou Province (No. 20050528), the Specialized Nomarch Research Fund for the Excellent Science and Technology and Education
Talent’s Projects of Guizhou Province, the Scientific and Technological Projects for the Returned Overseas Chinese Scholars,
Guizhou Province (Grant No. (2004)03), and the Top Talent’s Scientific Research Project of Organization Department of Guizhou
Province. 相似文献
11.
The electronic structure, densities of states and optical properties of the stable orthorhombic BaSi2 have been calculated using the first-principle density function theory and pseudopotential method. The results show that
BaSi2 is an indirect semiconductor with the band gap of 1.086 eV, the valence bands of BaSi2 are mainly composed of Si 3p, 3s and Ba 5d, and the conduction bands are mainly composed of Ba 6s, 5d as well as Si 3p. The
static dielectric function ɛ
1(0) is 11.17, the reflectivity n
0 is 3.35, and the biggest peak of the absorption coefficient is 2.15×105 cm−1.
Supported by the National Natural Science Foundation of China (Grant Nos. 60566001 and 60766002), the Specialized Research
Fund for the Doctoral Program of Higher Education of China (Grant No. 20050657003), the Scientific Research Foundation for
the Returned Overseas Chinese Scholars, Ministry of Education of China (Grant No. (2005)383), the Specialized Fund of Nomarch
for Excellent Talent of Science and Technology of Guizhou Province (Grant No. Z053114), the Scientific and Technological Projects
for the Returned Overseas of Guizhou Province (Grant No. (2004)03), and the Top Talent’s Scientific Research Project of Organization
Department of Guizhou Province (Grant No. Z053123) 相似文献
12.
An efficient quantum secure direct communication protocol is presented over the amplitude damping channel. The protocol encodes
logical bits in two-qubit noiseless states, and so it can function over a quantum channel subjected to collective amplitude
damping. The feature of this protocol is that the sender encodes the secret directly on the quantum states, the receiver decodes
the secret by performing determinate measurements, and there is no basis mismatch. The transmission’s safety is ensured by
the nonorthogonality of the noiseless states traveling forward and backward on the quantum channel. Moreover, we construct
the efficient quantum circuits to implement channel encoding and information encoding by means of primitive operations in
quantum computation.
Supported by the National Natural Science Foundation of China (Grant Nos. 60873191 and 60821001), the Specialized Research
Fund for the Doctoral Program of Higher Education (Grant No. 200800131016), the Natural Science Foundation of Beijing (Grant
No. 4072020), the National Laboratory for Modern Communications Science Foundation of China (Grant No. 9140C1101010601), and
the ISN Open Foundation 相似文献
13.
Influence of patterned TiO2/SiO2 dielectric multilayers for back and front mirror facetson GaN-based laser diodes 下载免费PDF全文
Ridge InGaN multi-quantum-well-structure (MQW) edge-emitting laser diodes (LDs) were grown on (0001) sapphire substrates by low-pressure metal-organic chemical vapour deposition (MOCVD). The dielectric TiO2/SiO2 front and back facet coatings as cavity mirror facets of the LDs have been deposited with electron-beam evaporation method. The reflectivity of the designed front coating is about 50% and that of the back high reflective coating is as high as 99.9%. Under pulsed current injection at room temperature, the influences of the dielectric facets were discussed. The threshold current of the ridge GaN-based LDs was decreased after the deposition of the back high reflective dielectric mirrors and decreased again after the front facets were deposited. Above the threshold, the slope efficiency of the LDs with both reflective facets was larger than those with only back facets and without any reflective facets. It is important to design the reflectivity of the front facets for improving the performance of GaN-based LDs. 相似文献
14.
YANG YuGuang WEN QiaoYan & ZHU FuChen School of Computer Beijing University of Technology Beijing China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China School of Science Beijing University of Posts Telecommunications Beijing China National Key Laboratory for Modern Communications Chengdu China 《中国科学G辑(英文版)》2007,50(3):331-338
An efficient quantum secret sharing protocol with orthogonal product states in the 33 Hilbert space is presented. The particles in the orthogonal product states form two particle sequences. One sequence is sent to Bob and the other is sent to Charlie after rearranging the particle orders. With the help of Alice, Bob and Charlie make the corresponding local measurement to obtain the information of the or- thogonal product states prepared. This protocol has many distinct features such as great capacity and high efficiency. 相似文献
15.
Multiferroic NiFe2O4 (NFO)-BaTiO3 (BTO) bilayered thin films are epitaxially grown on (001) Nb-doped SrTiO3 (STO) substrates by pulsed-laser deposition (PLD). Different growth sequences of NFO and BTO on the substrate yield two kinds of epitaxial heterostructures with (001)-orientation, i.e. (001)-NFO/(001)-BTO/substrate and (001)- BTO/(001)-NFO/substrate. Microstructure studies from x-ray diffraction (XRD) and electron microscopies show differences between these two heterostructures, which result in different multiferroic behaviours. The heterostructured composite films exhibit good coexistence of both ferroelectric and ferromagnetic properties, in particular, obvious magnetoelectric (ME) effect on coupling response. 相似文献
16.
Fabrication of metal oxide nanostructures based on Atomic Force Microscopy lithography 总被引:1,自引:0,他引:1
XiaoYang Zhu Gang Cheng ShuJie Wang ShuXi Dai ShaoMing Wan XingTang Zhang ZuLiang Du 《中国科学G辑(英文版)》2008,51(10):1448-1454
Atomic Force Microscopy (AFM) mechanical lithography is a simple but significant method for nanofabrication. In this work,
we used this method to construct nanostructures on Pt/Cu bilayer metal electrodes under ambient conditions in air. The influence
of various scratch parameters, such as the applied force, scan velocity and circle times, on the lithography patterns was
investigated. The Pt-Cu-Cu
x
O-Cu-Pt nanostructure was constructed by choosing suitable scratch parameters and oxidation at room temperature. The properties
of the scratched regions were also investigated by friction force microscopy and conductive AFM (C-AFM). The I–V curves show symmetric and linear properties, and Ohmic contacts were formed. These results indicate that AFM mechanical lithography
is a powerful tool for fabricating novel metal-semiconductor nanoelectronic devices.
Supported by the National Natural Science Foundation of China (Grant No. 90306010), the Program for New Century Excellent
Talents in University of China (Grant No. NCET-04-0653), the National Basic Research Program of China (Grant No. 2007CB616911),
and the Science and Technology Department of Henan Province (Grant No. 072300420100) 相似文献
17.
Through phase transformation kinetic analysis and experimental observation, the δ/γ transformation occurring in the non-equilibrium peritectic Fe-4.33at.%Ni alloys was systematically investigated. According to JMA solid-state transformation kinetic theory, the Time-Temperature-Transformation (TTT) curves of the δ/γ transformation in peritectic Fe-Ni alloy were calculated. On this basis, the physical correlation between the δ/γ transformation and the initial undercooling of melt (△T) was elucidated. The results indicate that the change of △T can alter not only the overall δ/γ transformation pathways but also the transformation fraction with respect to each transformation mechanism. 相似文献
18.
Hawking radiation can be viewed as a process of quantum tunneling near the black hole horizon. When a particle with angular
momentum L ≠ ωa tunnels across the event horizon of Kerr or Kerr-Newman black hole, the angular momentum per unit mass a should be changed. The emission rate of the massless particles under this general case is calculated, and the result is consistent
with an underlying unitary theory.
Supported by the National Natural Science Foundation of China (Grant No. 10773002) and the National Basic Research Program
of China (Grant No. 2003CB716302) 相似文献
19.
The kinetic viscosities of superheated liquids on the Gd-based bulk glass-forming alloys are measured by an oscillating viscometer
in a high vacuum atmosphere. According to the viscosity data, the parameters of superheated liquid fragility, M, are calculated. Based on the values of M in Gd-and Pr-based (cited from the literature) glass-forming alloys, we find that there is a linear correlation between M and the absolute value of mixing enthalpy, |ΔH
mix|, in an alloy system with the same base element, and the larger M, the smaller |ΔH
mix|. The alloy with larger M exhibits the larger height of energy barriers separating the minima on the potential energy landscape.
Supported by the National Basic Research Program of China (973 Program) (Grant No. 2007CB613901), the National Natural Science
Foundation of China (Grant No. 50231040), the Natural Science Foundation of Shandong Province of China (Grant No. Z2004F02),
and the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20050422024) 相似文献
20.
It is a simple introduction to quantum entanglement and quantum operations. The authors focus on some applications of quantum
entanglement and relations between two-qubit entangled states and unitary operations. It includes remote state preparation
by using any pure entangled states, nonlocal operation implementation using entangled states, entanglement capacity of two-qubit
gates and two-qubit gates construction.
Supported by the National Fundamental Research Program of China (Grant No. 2001CB309306), the National Natural Science Foundation
of China (Grant Nos. 60621064 and 10674127) and the Innovation Funds from Chinese Academy of Sciences 相似文献