Pratik Roy^*, Saptarshi Sahoo, Amit Kumar Mandal, Indranil Basu

Journal of Quantum Computing, Vol.3, No.4, pp. 151-160, 2021, DOI:10.32604/jqc.2021.019864

Abstract Quantum Key Distribution seems very promising as it offers unconditional security, that’s why it is being implemented by the tech giants of the networking industry and government. Having quantum phenomenon as a backbone, QKD protocols become indecipherable. Here we have focused on the complexities of quantum key distribution and how this technology has contributed to secure key communication. This article gives an updated overview of this technology and can serve as a guide to get familiar with the current trends of quantum cryptography. More >

D. L. Khokhlov^*

Journal of Quantum Computing, Vol.2, No.3, pp. 147-150, 2020, DOI:10.32604/jqc.2020.014734

Abstract An interpretation of the entangled states is considered. Two-photon states of photon A on path a and photon B on path b with polarizations H, V are constructed. Two synchronized photons, 1 and 2, can take the paths a and b, with equal probability 50%. In the bases a, b and H, V, the states of the photons form the product states. In the basis 1, 2, the states of the photons form the entangled state. The states of the photons in the bases 1, 2; a, b; H, V are inseparable. The correlation of the photons due to the… More >

S. Abdel-Khalek^1,2,*, E. M. Khalil^1,3, Beida Alsubei¹, A. Al-Barakaty⁴, S. M. Abo Dahab⁵

CMC-Computers, Materials & Continua, Vol.66, No.3, pp. 2445-2456, 2021, DOI:10.32604/cmc.2021.013830

Abstract In this paper, we analyzed squeezing in the information entropy, quantum state fidelity, and qubit-qubit entanglement in a time-dependent system. The proposed model consists of two qubits that interact with a two-mode electromagnetic field under the dissipation effect. An analytical solution is calculated by considering the constants for the equations of motion. The effect of the general form of the time-dependent for qubit-field coupling and the dissipation term on the temporal behavior of the qubit-qubit entanglement, quantum state fidelity, entropy, and variance squeezing are examined. It is shown that the intervals of entanglement caused more squeezing for the case of… More >

Eman M. A. Hilal¹, E. M. Khalil^2,3,*, S. Abdel-Khalek^2,4

CMC-Computers, Materials & Continua, Vol.66, No.2, pp. 1227-1236, 2021, DOI:10.32604/cmc.2020.012659

Abstract The effect of the field–field interaction on a cavity containing two qubit (TQ) interacting with a two mode of electromagnetic field as parametric amplifier type is investigated. After performing an appropriate transformation, the constants of motion are calculated. Using the Schrödinger differential equation a system of differential equations was obtained, and the general solution was obtained in the case of exact resonance. Some statistical quantities were calculated and discussed in detail to describe the features of this system. The collapses and revivals phenomena have been discussed in details. The Shannon information entropy has been applied for measuring the degree of… More >

Yan Chang^{1, *}, Shibin Zhang¹, Lili Yan¹, Xueyang Li¹, Tian Cao¹, Qirun Wang²

CMC-Computers, Materials & Continua, Vol.65, No.1, pp. 879-896, 2020, DOI:10.32604/cmc.2020.010042

Abstract The secure key rate of quantum key distribution (QKD) is greatly reduced because of the untrusted devices. In this paper, to raise the secure key rate of QKD, a device-independent quantum key distribution (DIQKD) protocol is proposed based on hyper-entangled states and Bell inequalities. The security of the protocol is analyzed against the individual attack by an adversary only limited by the no-signaling condition. Based on the formalization of Clauser-Horne Shimony-Holt (CHSH) violation measurement on local correlation, the probability of a secure secret bit is obtained, which is produced by a pair of hyper-entangled particles. By analyzing the secure secret… More >

Tao Shang^{1, *}, Ran Liu¹, Jianwei Liu¹, Yafei Hou²

CMC-Computers, Materials & Continua, Vol.64, No.3, pp. 1629-1645, 2020, DOI:10.32604/cmc.2020.09820

Abstract Establishing entanglement is an essential task of quantum communication technology. Beyond entanglement, quantum discord, as a measure of quantum correlation, is a necessary prerequisite to the success of entanglement distribution. To realize efficient quantum communication based on quantum discord, in this paper, we consider the practical advantages of continuous variables and propose a feasible continuous-variable quantum network coding scheme based on quantum discord. By means of entanglement distribution by separable states, it can achieve quantum entanglement distribution from sources to targets in a butterfly network. Compared with the representative discrete-variable quantum network coding schemes, the proposed continuous-variable quantum network coding… More >

Tao Li¹, Qingsheng Yang^{1, *}, Lianhua Ma², Xiaojun Zhang^{2, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.123, No.3, pp. 995-1014, 2020, DOI:10.32604/cmes.2020.09152

Abstract Phase transition of hydrogel, which is polymerized by polymer network, can be regarded as the transition of polymer network stability. The stability of the polymer network might be changed when the external environment changed. This change will lead to the transformation of sensitive hydrogels stability, thus phase transition of hydrogel take place. Here, we present a new free density energy function, which considers the non-gaussianity of the polymer network, chains entanglement and functionality of junctions through adding Gent hyplastic model and Edwards-Vilgis slip-link model to Flory-Huggins theory. A program to calculate the phase transition temperature was written based on new… More >

Yan Chang^1,*, Shibin Zhang¹, Lili Yan¹, Guihua Han¹, Haiquan Song¹, Yan Zhang¹, Xueyang Li¹, Qirun Wang²

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 1005-1014, 2019, DOI:10.32604/cmc.2019.06297

Abstract Quantum authorization management (QAM) is the quantum scheme for privilege management infrastructure (PMI) problem. Privilege management (authorization management) includes authentication and authorization. Authentication is to verify a user’s identity. Authorization is the process of verifying that a authenticated user has the authority to perform a operation, which is more fine-grained. In most classical schemes, the authority management center (AMC) manages the resources permissions for all network nodes within the jurisdiction. However, the existence of AMC may be the weakest link of the whole scheme. In this paper, a protocol for QAM without AMC is proposed based on entanglement swapping. In… More >

Zhiguo Qu^1,*, Tiancheng Zhu², Jinwei Wang¹, Xiaojun Wang³

CMC-Computers, Materials & Continua, Vol.56, No.1, pp. 47-59, 2018, DOI: 10.3970/cmc.2018.02215

Abstract In this paper, a novel quantum steganography protocol based on Brown entangled states is proposed. The new protocol adopts the CNOT operation to achieve the transmission of secret information by the best use of the characteristics of entangled states. Comparing with the previous quantum steganography algorithms, the new protocol focuses on its anti-noise capability for the phase-flip noise, which proved its good security resisting on quantum noise. Furthermore, the covert communication of secret information in the quantum secure direct communication channel would not affect the normal information transmission process due to the new protocol’s good imperceptibility. If the number of… More >

B.J. Yang¹, K.J. Cho¹, G.M. Kim¹, H.K. Lee^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.103, No.5, pp. 343-365, 2014, DOI:10.3970/cmes.2014.103.343

Abstract The addition of carbon nanotubes (CNTs) to a matrix material is expected to lead to an increase in the effective electrical properties of nanocomposites. However, a CNT entanglement caused by the matrix viscosity and the high aspect ratio of the nanotubes often inhibits the formation of a conductive network. In the present study, the micromechanics-based model is utilized to investigate the effect of CNT agglomeration on the electrical conductivity and percolation threshold of nanocomposites. A series of parametric studies considering various shapes and curviness distributions of CNTs are carried out to examine the effects of entanglement on the electrical performance… More >