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91.
完全非相干白光一维光生伏打暗空间孤子   总被引:10,自引:1,他引:9       下载免费PDF全文
陆猗  刘思敏  郭儒  杨立森  黄春福  汪大云 《物理学报》2003,52(12):3075-3081
使用白炽灯作光源在LiNbO3∶Fe晶体内实验观察到一维白光光生伏打暗空间孤 子. 由奇数 和偶数初始条件分别产生了灰孤子和灰孤子对,它们所感应的波导能导向白光和相干光. 用 相干光清楚地探测到它们内部的多模结构. 该实验证明了白光光生伏打暗空间孤子的存在, 并指出了用完全非相干的白光暗孤子控制和导向相干光的可能性. 关键词: 光生伏打效应 自陷 完全非相干孤子 波导  相似文献   
92.
93.
We prove the existence of global smooth solutions near a given steady state of the hydrodynamic model of the semiconductors in a bounded domain with physical boundary conditions. The steady state and the doping profile are permitted to be of large variation but the initial velocity must be small. Two cases are considered. In the first one the problem is three-dimensional, the boundary conditions are insulating and the steady state velocity vanishes. In the second one, the problem is one-dimensional, the boundary is of contact type and the steady state velocity does not vanish.  相似文献   
94.
Experimental data on the effect of thallium and sodium impurities on the lattice heat conductivity of PbTe at room temperature are reported. Because the lattice of lead chalcogenides is strongly polarized near charged impurities, the effect of impurities on the lattice heat conductivity depends substantially on their charge state. This property of the material has been used to determine the charge state of the thallium impurity in PbTe. The results obtained argue for a model of quasi-local thallium-impurity states which assumes low electron-correlation energy at an impurity center. Fiz. Tverd. Tela (St. Petersburg) 40, 1206–1208 (July 1998)  相似文献   
95.
Ideas previously enunciated by the author about the physical interpretation of curvilinear space with torsion are developed. With the new equations describing the eigenstates of such a space, the static centrosymmetric solution for gravitational and electric fields can be made consistent with the Newton and Coulomb laws. The asymptotic behavior of the axisymmetric solution at infinity is studied. The gyromagnetic ratio obtained is characteristic of the electron. Ural State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, p. 56–60, May, 1998.  相似文献   
96.
We use the eikonal approximation to develop a general formula for the cross sections of inelastic collisions of multicharged fast ions (including relativistic ions) with atoms that is applicable within a broad range of collision energies, has the standard nonrelativistic limit, and becomes, in the ultrarelativistic case, the well-known result that follows from the exact solution of the Dirac equation. As an example we study the excitation and ionization of a hydrogenlike atom, the single and double excitation and ionization of a heliumlike atom, and multiple (up to the eighth order) ionization of the neon atom and (up to eighteenth order) ionization of the argon atom. We derive simple analytical expressions for the inelastic cross sections and establish recurrence relations linking the cross sections of ionization of different orders. Finally, we compare our results with the experimental data. Zh. éksp. Teor. Fiz. 114, 1646–1660 (November 1998)  相似文献   
97.
陈理  侯明山 《波谱学杂志》1991,8(3):275-282
在氢化丁苯共聚物13C-NMR谱脂肪碳部分谱带归属的基础上,根据各谱带的主要来源,推导出六个二单元浓度的计算公式。计算出二单元、一单元的相对含量,各结构单元的数均序列长度、嵌段含量和其它结构参数。加氢前后的1H-和13C-NMR谱的组成计算结果基本一致。初步探讨了作为粘度指数改进剂的氢化丁苯共聚物微观结构与性能的关系,为合成提供了依据。  相似文献   
98.
本文研究了铁矿石、铬矿石、锰矿石中的微量磷的电感耦合等离子体发射光谱法的测定。方法简便,具有很好的精密度和准确度。标准样品的分析结果基本与标称值相吻合,回收率在95%-105%之间。  相似文献   
99.
Some corollaries of the Hirzebruch-Thom signature theorem are discussed. The multiplicativity of the signature and the naturalness of the Pontryagin classes for coverings in the case of ℚ-homology manifolds is proved. A geometric proof of Hirzebruch’s well-known “functional equation” for the virtual signature is outlined. Bibliography: 25 titles. Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 231, 1995, pp. 197–209. Translated by N. Yu. Netsvetaev.  相似文献   
100.
The concentration and chemical state of copper in the subsurface region of Cu/SiO2 composite films obtained by simultaneous magnetron sputtering from two sources (Cu and SiO2) are determined by x-ray photoelectron spectroscopy (XPS). It is established that copper in the as-grown film is primarily in the form of unoxidized atoms dispersed in a SiO2 matrix. Annealing of the film results in practically no oxidation, but about 70% of the copper atoms condense into metallic clusters with sizes below 10 Å in the subsurface region and about 50 Å in the bulk of the film. The changes in the binding energy of core electrons, and especially in the energies of Auger electrons, are so large in this situation that photoelectron and Auger spectroscopy are efficient methods for monitoring the chemical state of this composite material.  相似文献   
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