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991.
We present an optical scheme to almost completely teleport a bipartite entangled coherent state using a four-partite cluster-type entangled coherent state as quantum channel. The scheme is based on optical elements such as beam splitters, phase shifters, and photon detectors. We also obtain the average fidelity of the teleportation process. It is shown that the average fidelity is quite close to unity if the mean photon number of the coherent state is not too small. 相似文献
992.
A competition model of three species in exchange-driven aggregation growth is proposed. In the model, three distinct aggregates grow by exchange of monomers and in parallel, birth of species A is catalyzed by species B and death of species A is catalyzed by species C. The rates for both catalysis processes are proportional to kj^v and ky respectively, where ν(ω) is a parameter reflecting the dependence of the catalysis reaction rate of birth (death) on the catalyst aggregate's size. The kinetic evolution behaviors of the three species are investigated by the rate equation approach based on the mean-field theory: The form of the aggregate size distribution of A-species αk(t) is found to be dependent crucially on the two catalysis rate kernel parameters. The results show that (i) in case of ν ≤O, the form of ak (t) mainly depends on the competition between self-exchange of species A and species-C-catalyzed death of species A; (ii) in case of ν 〉 0, the form of αk(t) mainly depends on the competition between species-B-catalyzed birth of species A and species-C-catalyzed death of species A. 相似文献
993.
Based on the Dirac equation describing an electron moving in a uniform and cylindrically symmetric magnetic field which may be the result of the self-consistent mean field of the electrons themselves in a neutron star, we have obtained the eigen solutions and the orbital magnetic moments of electrons in which each eigen orbital can be calculated. From the eigen energy spectrum we find that the lowest energy level is the highly degenerate orbitals with the quantum numbers pz = 0, n = 0, and m ≥0. At the ground state, the electrons fill the lowest eigen states to form many Landau magnetic cells and each cell is a circular disk with the radius λfree and the thickness λe, where λfree is the electron mean free path determined by Coulomb cross section and electron density and λe is the electron Compton wavelength. The magnetic moment of each cell and the number of cells in the neutron star are calculated, from which the total magnetic moment and magnetic field of the neutron star can be calculated. The results are compared with the observational data and the agreement is reasonable. 相似文献
994.
Influences of Bi2O3/V2O5 Additives on the Microstructure and Magnetic Properties of Lithium Ferrite 下载免费PDF全文
Lithium ferrite materials with different concentrations of Bi2O3 and V2O5 additives are prepared by the conventional ceramic technique. The x-ray diffraction analysis proves that the additives do not affect the final crystal phase of the lithium ferrite in our testing range. Both Bi2O3 and V2O5 additives could promote densification and lower sintering temperature of the lithium ferrite. The average grain size first increases, and then gradually decreases with the Bi2O3 content. The maximal grain size appears with 0.25 wt% Bi2O3. The average grain size first increases, and then is kept almost unchanged with the V2O5 content. The maximal average grain size of the samples with V2O5 additive is much smaller than that of the samples with Bi2O3 additive. Furthermore, the V2O5 additive more easily enters the crystal lattice of the lithium ferrite than the Bi2O3 additive. These characteristics evidently affect the magnetic properties, such as saturation flux density, ratio of remanence Br to saturation flux density Bs, and coercive force of the lithium ferrite. The mechanisms involved are discussed. 相似文献
995.
We simulate the spectrum characteristics of fibre Bragg grating (FBG) with non-uniform temperature using the transmission matrix method, and the results are analysed. It is found that firstly the modulated coefficient of average refractive index is a very important parameter that influences the spectrum characteristic of the fibre Bragg grating, and secondly the spectrum curves are different in different temperature fields at the same parameter. Hence, we can determine the metrical temperature by analysing the spectrum of fibre Bragg grating. 相似文献
996.
We calculate the binding energy per baryon of the A hypernuclei systematically, using the relativistic mean field theory (RMF) in a static frame. Some similar properties are found for most of the A hypernuclei confirmed by experiments. The data show that a A hypernueleus will be more stable if it is made by adding a A hyperon to a stable normal nuclear core, or by replacing a neutron by a A hyperon to a stable normal nuclear core. According to our calculations, the existence of some new A hypernuclei are predicted under the frame of RMF. 相似文献
997.
A three-company econophysics model for competing multi-agent systems in a triangular lattice is analyzed using mean field theory for its phase diagram. Interpretations for the temperature, spin density and lattice structures are presented. Suggestions for the use of this model for econophysics in the context of multi-agent systems are made. 相似文献
998.
介绍了低吸收高负载特性的全氟碳化合物SBS新介质,研究了SBS相位共轭镜和SBS光限幅器对新介质的选取原则,并在Nd: YAG调Q激光器中进行了实验验证.结果表明,SBS相位共轭镜需要平均分子量小,运动黏度小,增益系数大的介质;而SBS光限幅器需要平均分子量大,运动黏度大,增益系数小的介质.新介质的发现增加了SBS介质的种类,而介质的选取原则对新介质的选用打下了良好的基础.
关键词:
SBS新介质
选取原则
平均分子量
运动黏度 相似文献
999.
1000.
利用统一色噪声近似理论,研究乘性色噪声和加性色噪声驱动的非对称双稳系统中,势阱的非对称性和噪声对系统两个方向的平均第一穿越时间T+(xs1→xs2)和T-(xs2→xs1)的影响(xs1和xs2是双稳系统的两个稳定点).数值结果表明:T+(xs1→xs2)随乘性噪声的自关联时间τ1以及加性噪声的自关联时间τ2的增大而减小.T-(xs2→xs1)随乘性噪声的自关联时间τ1以及加性噪声的自关联时间τ2的增大而增大.在曲线(T+(xs1→xs2),λ)和(T-(xs2→xs1),λ)上都存在单峰.T+(xs1→xs2)随非对称系数r的增大而增大,T-(xs2→xs1)随非对称系数r的增大而减小.
关键词:
统一色噪声近似
平均第一穿越时间
加性色噪声
乘性色噪声 相似文献