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961.
多光子J-C模型的场熵的演化 总被引:5,自引:0,他引:5
研究了一个二能级原子与相干光场多光子相互作用下场熵演化的动力学特性 相似文献
962.
A. G. Aleksandrov 《Functional Analysis and Its Applications》2005,39(4):245-255
We introduce the notion of logarithmic index of a vector field on a hypersurface and prove that the homological index can be expressed via the logarithmic index. Then both invariants are described in terms of logarithmic differential forms for Saito free divisors, which are hypersurfaces with nonisolated singularities, and all contracting homology groups of the complex of regular holomorphic forms on such a hypersurface are computed. In conclusion, we consider the case of normal hypersurfaces, including the case of an isolated singularity, and describe the contracting homology of the complex of regular meromorphic forms with the help of the residue of logarithmic forms. 相似文献
963.
Marzena Ciemala Kazimierz Szymiczek 《Proceedings of the American Mathematical Society》2005,133(9):2519-2523
We prove that the kernel of the ring homomorphism between the Witt ring of any order of a global field and the Witt ring of the field is a nilideal.
964.
965.
1IntroductionThegeometricphaseplaysanimportantroleinunderstandingsomeoftheoutstandingenigmasofquantummechanics,andithaspaidmu... 相似文献
966.
Zhi-Yong Jiao Jun-Mao Ma Ning Li Xia Fu 《International Journal of Theoretical Physics》2008,47(11):2841-2849
In this paper, we investigate entropy properties of the single-mode binomial field interacting with the two entangled two-level
atoms. It is found that the different initial conditions lead to the different evolutions of entropy of the binomial field. 相似文献
967.
A unification of some factorization results regarding products of positive-definite matrices, commutators, and products of involutions is presented. This topic was first presented by Sourour for fields with, in the latter two classes, sufficiently many elements in terms of the order of the matrix being factored. The current presentation is valid for matrices over any field with at least four elements, and is independent of the order of the matrix being factored. 相似文献
968.
969.
We introduce a general method in order to construct the nonchiral fusion rules which determine the operator content of the operator product algebra for rational conformal field theories. We are particularly interested in the models of the complementary D-like solutions of the modular invariant partition functions with cyclic center Z
N
. We find that the nonchiral fusion rules have a Z
N
-grading structure. 相似文献
970.
R. Valenzuela G. Alvarez H. Montiel M.P. Gutirrez M.E. Mata-Zamora F. Barrn A.Y. Snchez I. Betancourt R. Zamorano 《Journal of magnetism and magnetic materials》2008,320(14):1961-1965
A low-field non-resonant microwave absorption has recently been observed in a variety of magnetically ordered materials at low DC fields (−1000 Oe HDC+1000 Oe), which is known as low-field microwave absorption (LFA). It has been shown that LFA is essentially similar to giant magnetoimpedance (GMI), and clearly different from ferromagnetic resonance (FMR). LFA strongly depends on the anisotropy field of the sample. In contrast with FMR (which can be described as the homogeneous precession of spins in the saturated state), LFA can be thought as a spin rotation process occurring during the magnetic saturation. In this work, we present a detailed study of the basic features of LFA in several types of materials: ferrites and amorphous microwires and ribbons; in particular the effects sample shape, temperature up to the Curie transition, the influence of easy axis and the effects of annealings. These examples show that once LFA is fully understood, it can become a powerful characterization tool. 相似文献