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81.
Both charged colloidal suspensions and complex (dusty) plasmas represent classical many-body strongly coupled Coulomb systems. Here we discuss their basic properties and focus on their heterogeneous crystallization from an undercooled melt. In particular, a model with different mobilities is proposed which is realizable in binary mixtures of charged particles. Within this binary-mobility model, the crystallization behaviour near a structured wall is explored by Brownian dynamics computer simulations. As a result, the propagation velocity of the crystal-fluid interface is a nonmonotonic function of the mobility ratio (if expressed in terms of an averaged mobility). 相似文献
82.
In this paper, the electronic transport of La(0.7)(Sr,Ca)(0.3)MnO(3) films grown by pulsed laser deposition on a LaAlO(3)(001) substrate with deep parallel structured steps and a 30° symmetric bicrystal SrTiO(3)(001) substrate have been discussed. The electronic transport properties have been related to the well-known extrinsic transport of bulk manganite compounds. The spin-glass-like behavior with a characteristic peak at 20 K and domain formation at the grain boundary is observed. Further, it has been quantified from the resonant tunneling model that mixed magnetic interactions play a significant role in the manganite films deposited on step edges. 相似文献
83.
We consider intrinsic contributions to the spin Hall and spin Nernst effects in a bilayer graphene. The relevant electronic spectrum is obtained from the tight binding Hamiltonian, which also includes the intrinsic spin-orbit interaction. The corresponding spin Hall and spin Nernst conductivities are compared with those obtained from effective low-energy k ?p and reduced Hamiltonians, which are appropriate for states in the vicinity of the Fermi level of a neutral bilayer graphene. Both conductivities are determined within the linear response theory and Green function formalism. The influence of an external voltage between the two atomic sheets is also considered. The results reveal a transition from the topological spin Hall insulator phase at low voltages to conventional insulator phase at larger voltages. 相似文献
84.
The effect of LaFeO(3) addition to Bi(1/2)(Na(0.78)K(0.22))(1/2)TiO(3) ceramics on the phase stability and macroscopic functional properties was investigated. Similarly to other chemical modifiers known in the literature, LaFeO(3) addition suppresses an electric-field-induced long-range ferroelectric order, giving rise to a giant unipolar strain of ~0.3% at 2?mol% LaFeO(3) addition. Time-dependent changes in polarization and strain hysteresis loops both during successive electrical cycling and after removal of the electric field suggest that a specimen with 2?mol% LaFeO(3) consists of both ergodic and nonergodic phases, which is unique among the known relaxor materials. 相似文献
85.
86.
We study the effect of electric field and magnetic flux on spin entanglement in an artificial triangular molecule built of coherently coupled quantum dots. In a subspace of doublet states an explicit relation of concurrence with spin correlation functions and chirality is presented. The electric field modifies superexchange correlations and shifts many-electron levels (the Stark effect), as well as changing spin correlations. For some specific orientation of the electric field one can observe monogamy, for which one of the spins is separated from two others. Moreover, the Stark effect manifests itself in a different spin entanglement for small and strong electric fields. The role of magnetic flux is opposite: it leads to circulation of spin supercurrents and spin delocalization. 相似文献
87.
Qing L? Ming Hua LIU* Laboratory of Colloid Interface Science Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences 《中国化学快报》2001,(12)
Langmuir monolayer at the air/water interface is the basis to understand the molecular arrangement and to fabricate the organized molecular films1. Bolaamphiphiles describes the molecules in which two head functional groups are linked by one or two hydrophobic chains2,3. In comparison with the one-headed amphiphile, abundant configurations of Langmuir monolayer are expected in bolaamphiphiles. Generally, three kinds of configurations of the Langmuir monolayers of bolaamphiphile at the air/w… 相似文献
88.
KAN Zi-Guia b CHENG Wen-Dana? WU Dong-Shenga ZHANG Haoa GONG Ya-Jinga ZHU Jinga TONG Hua-Nana a 《结构化学》2005,24(12):1468-1475
1 INTRODUCTION stand the chemical bonding properties and electronic origins of optical transition for solid In(PO3)3, the During the past decades, many indium phosphates crystal energy band and optical response functions have been reported and researched on their conduc- are also calculated. tivity anisotropy, band structure and optical proper- ties[1, . However, to our current knowledge, the com- 2] 2 EXPERIMENTALAND pounds containing alkaline-earth metals are rarely COMPUTATIO… 相似文献
89.
多模噪声理论及其在通信保密中的应用 总被引:2,自引:0,他引:2
给出了一种比较通用的非高斯噪声模型——多模噪声,采用无惯性非线性变换器给出了多模噪声中信号的检测与估计方法,该方法对概率密度函数形状对称的噪声是普遍适用的。在此基础上设计了可用于通信保密的多模噪声,说明了本加密方法适用于无线通信信道加密,并从统计分析的角度研究了可能的密码分析方法。 相似文献
90.
近年来,随着人们生活水平不断提高,对地面数字电视广播系统提出了更高的要求.为了规范我国地面数字电视广播系统的管理,使地面数字电视广播能够高效运行,广播部门必须不断完善地面数字广播电视系统的监测制度. 相似文献