共查询到20条相似文献,搜索用时 93 毫秒
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光束在非局域非线性介质中的传输过程由非局域非线性薛定谔方程描述.1+2D非局域非线性薛定谔方程可以转化为圆柱坐标系下的变分问题.通过展开介质响应函数并合理假设试探解求解变分方程,得到光束在强非局域非线性介质中的拉盖尔-高斯解.满足一定条件时,拉盖尔-高斯光束将形成光孤子或退化为高斯光束.
关键词:
非局域非线性介质
强非局域性
变分法
拉盖尔-高斯光束 相似文献
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本文在多通道量子亏损理论框架下,利用相对论多通道理论,计算了铥原子收敛于4f13(2F7/2o)6s(7/2,1/2)4o和4f13(2F7/2o)6s(7/2,1/2)3o的三个偶宇称里德伯系列.通过将计算结果与美国国家标准与技术研究院数据进行比较,展示了两种类型的电子关联效应:1)里德伯系列之间的相互作用,导致里德伯系列的能级出现整体偏移;2)一个孤立的干扰态镶嵌在一个里德伯系列中,破坏了该里德伯系列能级的规则性. 相似文献
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We review the construction of the multiparametric quantum group ISOq,r(N) as a projection from SOq,r (N + 2) and show that it is a bicovariant bimodule over SOq,r(N). The universal enveloping algebra Uq,r(iso(N)), characterized as the Hopf algebra of regular functionals on ISOq,r(N), is found as a Hopf subalgebra of Uq,r(so(N + 2)) and is shown to be a bicovariant bimodule over Uq,r(so(N)).
An R-matrix formulation of Uq,r(iso(N)) is given and we prove the pairing Uq,r(iso(N)) — ISOq,r(N)). We analyze the subspaces of Uq,r(iso(N)) that define bicovariant differential calculi on ISOq,r(N). 相似文献
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F.P. Temme 《Molecular physics》2013,111(5):883-905
NMR aspects of finite group natural-embeddings in higher n-fold spin algebras over Hilbert space are considered in the context of icosahedral cage clusters associated with specific 11B borohydride, -deuteride anions for which n = 12. The focus of the discussion is on the abstract and physical models derived from permutation modules in the form of λ ├ n partitions over , where . Hence, the related Kostka expansion coefficients from the pure abstract spin space of mapping and other -combinatorial aspects, including the nature of inner tensor products arising in the high-n limit, are especially pertinent. Further insight into spin cluster NMR problems is provided by studies of -induced algebras derived from the [λSA] self-associated irreps. Motivation for the work comes from its potential physical applications for higher-n bi-cluster NMR problems, e.g., in spin dynamics. The representational properties derived are essential in understanding the structure of Liouville space for both SU(2) and higher spin SU(m) clusters. The Hilbert space aspects presented here impact strongly on the somewhat neglected question of the nature of subduction, i.e., involving a finite group naturally embedded in a higher group, within an implicit dual Racah symmetry chain. The essential mappings presented here include both the λ module-onto-{[λ′]} set and the aspects, where the Kostka integers of the former arise naturally in the realization of λ module mappings over . 相似文献
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《Physica A》1995,220(3-4):585-598
An antiferromagnetic equivalent-neighbour Heisenberg interaction Hi between impurity spins is added to the reduced s-d Hamiltonian Hr previously introduced by simplifying the Kondo s-d exchange Hamiltonian HK. Asymptotic mean-field theory is developed for Hr + Hi, in the presence and absence of external magnetic field, and applied to (La1−xCex)Al2 alloys. Specific heat ci(T) and zero-field susceptibility χi(0,T) curves for (La1−xCex)Al2 are depicted. The coupling constants of Hr + Hi and conduction bandwidth are adjusted so that Tc temperatures for x = 0.2, 0.1 are equal to the experimental values. ci(T) exhibits a jump at Tc and is decreasing for T < Tc. χi(0,T) has a first order pole at Tc which corresponds to the maximum of experimental susceptibility and χi(0,0) > 0. These results improve those obtained earlier on the grounds of Hr theory. 相似文献
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Yu Wang Yuan-Ming Zhai Kai Ke Wei Yang Ming-Bo Yang 《Journal of Macromolecular Science: Physics》2013,52(1):123-131
The characteristic shear rate for nonlinear viscoelastic behavior in a polydisperse polymer system was investigated by the study of the stress overshoot behavior of polybutadiene solutions. The frequency at the crossing point of the dynamic moduli () was determined by oscillation frequency sweeps. For the stress overshoot observed in the shear flow at a fixed rate, the dependency of the stress drop, , defined as the difference between the stress at the peak and the stress at the steady state, on the shear rate can be well described by a fitting function: , and a critical shear rate () can be obtained using this fitting function. The correlation between and for the solutions can be expressed as and the proportionality factor is dependent on the degree of chain interpenetration. When the shear rate was normalized by , the dependency of the stress drop on this normalized shear rate for the solutions with different concentrations can be superposed well. This observation indicates that can be viewed as a characteristic shear rate for nonlinear viscoelastic behavior in a polydisperse polymer solution. 相似文献
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We study the discrete Painlevé equations associated to the affine Weyl group which can be obtained by the implementation of a special limits of -associated equations. This study is motivated by the existence of two -associated discrete both having a double ternary dependence in their coefficients and which have not been related before. We show here that two equations correspond to two different limits of a -associated discrete Painlevé equation. Applying the same limiting procedures to other -associated equations we obtained several -related equations most of which have not been previously derived. 相似文献