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31.
HE Guang-Qiang ZENG Gui-Hua 《理论物理通讯》2006,46(1):61-64
A quantum encryption protocol based on Gaussian-modulated continuous variable EPR correlations is proposed. The security is guaranteed by continuous variable EPR entanglement correlations produced by nondegenerate optical parametric amplifier (NOPA). For general beam splitter eavesdropping strategy, the mutual information I(α, ε) between Alice and Eve is caJculated by employing Shannon information theory. Finally the security analysis is presented. 相似文献
33.
Examples are worked out using a new equation proposed in the previous paper to show that it has new physical predictions for mesoscopic systems. 相似文献
34.
35.
X-ray diffraction patterns of nanocrystalline Fe-Cu-Nb-Si-B (FINEMET) alloys reveal that bcc α-Fe/α-FeSi crystallites with
the average grain size of 20(5) nm are dispersed in amorphous matrix. Enhanced electron—electron interaction (EEI) and quantum
interference (QI) effects as well as electron-magnon (and/or electron-spin fluctuation) scattering turn out to be the main
mechanisms that govern the temperature dependence of resistivity. Of all the inelastic scattering processes, inelastic electron-phonon
scattering is the most effective mechanism to destroy phase coherence of electron wave functions. The diffusion constant,
density of states at the Fermi level and the inelastic scattering time have been estimated, for the first time, for the alloys
in question
Article presented at the International Symposium on Advances in Superconductivity and Magnetism: Materials, Mechanisms and
Devices, ASMM2D-2001, 25–28 September 2001, Mangalore, India. 相似文献
36.
A. Khrennikov 《Annalen der Physik》2003,12(10):575-585
We study the probabilistic consequences of the choice of the basic number field in the quantum formalism. We demonstrate that by choosing a number field for a linear space representation of quantum model it is possible to describe various interference phenomena. We analyse interference of probabilistic alternatives induced by real, complex, hyperbolic (Clifford) and p‐adic representations. 相似文献
37.
38.
A series of low density polyethylene systems has been studied with respect to structural evolution and short-term dielectric breakdown behaviour. All materials were based upon a single polymer, that is commonly used in high voltage applications, but with different additives. In all three of these systems, multiple melting transitions were observed, as a result of molecular fractionation effects during crystallization. In the virgin polymer, a space-filling banded spherulitic morphology was found to develop at low temperatures (102 °C and below) whereas, at higher temperatures, only a few isolated axialites were observed. Inclusion of the antioxidant resulted in greatly increased nucleation densities, such that, at low temperatures, no evidence of spherulitic organisation remained. At higher temperatures, sheaf-like lamellar aggregates developed, which were much smaller and much more numerous than in the case of the virgin polymer. Further addition of dicumyl peroxide (DCP) resulted in the rapid formation of a crosslinked network at 200 °C. Some crosslinking also occurred at 150 °C, but over a much longer timescale. Where extensive crosslinking occurred prior to crystallization, the resulting gel inhibited structural development, such that only a few small, isolated sheaves were able to form at 102 °C. In view of the principal application area of this material, the breakdown strength of each of the above systems was then measured and the whole data set was analysed statistically. When structural factors were considered alongside the statistics, no clear trends emerged to indicate that either the compositional or morphological variations were reflected in the short-term electrical failure processes. 相似文献
39.
M. Castagnino R. Id Betan R. Laura 《International Journal of Theoretical Physics》2003,42(10):2423-2439
By extending the notion of mixed states to functionals acting on the space of observables with diagonal singularity we obtain a well-defined complex spectral decomposition of the time evolution for a quantum decaying system. In this formalism, generalized Gamow states are obtained with well-defined physical properties. 相似文献
40.
Dimitar I. Pushkarov 《Central European Journal of Physics》2004,2(3):420-455
Basic ideas and results which characterize quantum diffusion of defects in quantum crystals like solid helium as a new phenomenon
are presented. Quantum effects in such media lead to a delocalization of point defects (vacancies, impurities etc.) and they
turn into quasiparticles of a new type—defectons, which are characterized not by their position in the crystal lattice but
by their quasimomentum and dispersion law. Defecton-defecton and defecton-phonon scattering are considered and an interpolation
formula for the diffusion coefficient valid in all interesting temperature and concentration regions is presented. A comparison
with the experimental data is made. Some alternative points of view are discussed in detail and the inconsistency of the Kisvarsanyi-Sullivan
theory is shown. 相似文献