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991.
Simple Entanglement Measure for Multipartite Pure States 总被引:3,自引:0,他引:3
Feng Pan Feng Pan Feng Pan Dan Liu Guoying Lu J. P. Draayer 《International Journal of Theoretical Physics》2004,43(5):1241-1247
A simple entanglement measure for multipartite pure states is formulated based on the partial entropy of a series of reduced density matrices. Use of the proposed new measure to distinguish disentangled, partially entangled, and maximally entangled multipartite pure states is illustrated. 相似文献
992.
Chessboard-like substrates are introduced in this paper, in order to study the diffusion-limited aggregation (DLA)and the motion of poly-atoms on heterogeneous surfaces. The effect of morphology of such substrates upon the cluster aggregation is investigated using the Monte Carlo simulation. It is found that the growth process and the cluster morphology are governed by the energetic topography of the substrates. Our simulation also indicate that the island density and the fractal dimension of the clusters depend strongly on the substrate topography and the activation energy. 相似文献
993.
We investigate the properties of waveguides induced by one-dimensional grey
screening solitons in biased photorefractive crystals. The results show that
waveguides induced by grey screening solitons are always of single mode for all
intensity ratios, i.e. the ratios between the peak intensity of the
soliton and the dark irradiance. Our analysis indicates that the
energy confined near the centre of the grey soliton and the propagation constant of
the guided mode of the waveguide induced by the grey screening soliton
increase monotonically with intensity ratio increasing. On the other hand,
when the soliton greyness increases, the energy confined near the centre
of the grey soliton and the propagation constant of the guided mode of the
waveguide induced by the grey screening soliton decrease monotonically.
Relevant examples are provided where photorefractive crystal is of the
strontium barium niobate type. 相似文献
994.
Raman spectra of ceramic Sr2Bi4Ti5O18 (SBTi5) are reported to consist of four different Raman bands. Temperature-dependent spectra reveal the relationship between the lattice vibration and the material's structure. There appears a relatively large change in structure of the material at about 273K, The anharmonic potential of the material has a great influence on its phonon mode full width at half maximum (FWHM), which can be expressed by a function of temperature. Theoretical fittings of the FWHMs for the two modes at around 312 cm^-1 and 464cm^-1 indicate that the latter phonon mode is more anharmonic than the former one. 相似文献
995.
In this paper, we derive an explicit analytic expression of the
relative entropy between two general Gaussian states. In the
restriction of the set for Gaussian states and with the help of
relative entropy formula and Peres--Simon separability criterion,
one can conveniently obtain the relative entropy entanglement for
Gaussian states. As an example, the relative entanglement for a
two-mode squeezed thermal state has been obtained. 相似文献
996.
采用新型贵金属铱的配合物bis(1,2-dipheny1-1H-benzoimida-zole)iridium (acetylacetonate)作为磷光敏化剂,与荧光染料4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-en-yl)-4H-pyran共同掺杂到聚合物主体材料poly(N-vinylcarbazole)中,以N,N'-diphenyl-N,N'-bis(1-naphthyl) (1,1'-biphenyl)-4,4'-diami-ne作为蓝光发光层,制备了白色有机电致发光器件. 通过对掺杂体系的紫外-可见吸收光谱、光致发光光谱以及电致发光光谱的表征,分析了该磷光敏化体系的能量转移机制. 结果表明,在该聚合物磷光荧光双掺杂体系中,由于磷光与荧光材料之间的不完全的F?rster能量传递过程,导致电致发光光谱中同时存在磷光材料三线态到基态与荧光材料单线态到基态的辐射衰减发光. 该掺杂体系成功实现了白光发射,随着偏置电压的升高,器件的CIE色坐标有微小的红移,但都非常接近等能白光点,器件表现出了很好的色纯度. 相似文献
997.
Spatial coherence resonance on diffusive and small-world networks of Hodgkin-Huxley neurons 总被引:1,自引:0,他引:1
Spatial coherence resonance in a spatially extended system that is locally modeled by Hodgkin-Huxley (HH) neurons is studied in this paper. We focus on the ability of additive temporally and spatially uncorrelated Gaussian noise to extract a particular spatial frequency of excitatory waves in the medium, whereby examining the impact of diffusive and small-world network topology that determines the interactions amongst coupled HH neurons. We show that there exists an intermediate noise intensity that is able to extract a characteristic spatial frequency of the system in a resonant manner provided the latter is diffusively coupled, thus indicating the existence of spatial coherence resonance. However, as the diffusive topology of the medium is relaxed via the introduction of shortcut links introducing small-world properties amongst coupled HH neurons, the ability of additive Gaussian noise to evoke ordered excitatory waves deteriorates rather spectacularly, leading to the decoherence of the spatial dynamics and with it related absence of spatial coherence resonance. In particular, already a minute fraction of shortcut links suffices to substantially disrupt coherent pattern formation in the examined system. 相似文献
998.
For any finite-dimensional semisimple Lie algebra g, a
Z+-graded vertex algebra is construsted on the vacuum
representation Vk(\hat{g}[ θ]) of \hat{g}[θ], which is
a one-dimentional central extension of θ-invariant subspace on the loop algebra
Lg=g\otimes C((t1/p)). 相似文献
999.
在氢气和甲烷环境下,利用辉光等离子体放电制备了聚合物。该聚合物的外观特征为白色、略发黄、柔软、丝状,易碎为粉末状。聚合物中含有–CH3,–CH2,C–O,–C=C–,–OH等官能团且不存在单质形态的碳。有机溶剂溶解分析发现,常温下该聚合物在各种有机溶剂中的溶解性极小、小于0.1mg.ml-1,几乎不溶于甲苯中,在不同有机溶剂中的溶解度大小依次为,S丙酮>S三氯甲烷>S乙醇>S环己醇>S甲苯。低温等离子体的离化率越高、中性气体被极化时的极化半径越大、环境温度越低以及介电常数越小,聚合物的生成能力越强。 相似文献
1000.
The well-known Fraunhofer multi-slit diffraction is described as the multi-slit interference modulated by the singleslit diffraction, namely the multiplication between the single-slit diffraction factor and the multi-slit interference factor. By considering the simplified argument we show that the multi-slit diffraction of evanescent waves which are in the near-field region also has the interference and diffraction effects, and that this two-fold effect can be expressed as the convolution of the diffraction factor and the interference factor. Our conclusion could be helpful to understand the contribution of evanescent waves to the optical responses of sub-wavelength structures such as slits and grooves. 相似文献