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A complex symplectic structure on a Lie algebra h is an integrable complex structure J with a closed non-degenerate (2,0)-form. It is determined by J and the real part Ω of the (2,0)-form. Suppose that h is a semi-direct product g?V, and both g and V are Lagrangian with respect to Ω and totally real with respect to J. This note shows that g?V is its own weak mirror image in the sense that the associated differential Gerstenhaber algebras controlling the extended deformations of Ω and J are isomorphic. 相似文献
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The ideality factor n and the barrier height Φap of the sputtered Ni/p-InP Schottky diodes have been calculated from their experimental Current–voltage (I–V) characteristics in the temperature range of 60–400 K with steps of 10 K. The n and Φap values for the device have been obtained as 1.27 and 0.87 eV at 300 K and 1.13 and 0.91 eV at 400 K, respectively. The n values larger than unity at high temperatures indicate the presence of a thin native oxide layer at the semiconductor/metal interface. The barrier height (BH) has been assumed to be bias dependent due to the presence of an interfacial layer and interface states located at the interfacial layer-semiconductor interface. Interfacial layer-thermionic emission current mechanism has been fitted to experimental I–V data by considering the bias-dependence of the BH at each temperature. The best fitting values of the series resistance Rs and interface state density Ns together with the bias-dependence of the BH have been used at each temperature, and the Rs and Ns versus temperature plots have been drawn. It has been seen that the experimental and theoretical forward bias I–V data are in excellent agreement with each other in the temperature range of 60–400 K. It has been seen that the Rs and Ns values increase with a decrease in temperature, confirming the results in the literature. 相似文献
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Sadia Ameen M. Shaheer Akhtar S.G. Ansari O-Bong Yang Hyung-Shik Shin 《Superlattices and Microstructures》2009
A p–n heterostructure diode of polyaniline (PANI) and ZnO nanoparticles was prepared by the electrophoretic deposition of PANI on ZnO nanoparticles thin film coated fluorine doped tin oxide (FTO) glass at room temperature. The morphological, structural and optical studies substantiated the penetration, bonding and the interaction of PANI molecules with ZnO nanoparticles thin film substrates. The prominent blue shift in UV-Vis spectra indicated the strong interaction between ZnO and PANI through the decreased degree of orbital overlap between π electrons of the phenyl rings with the lone pair of the nitrogen atom in the PANI molecules. The I–V characteristics of PANI/ZnO heterostructure diode showed weak rectifying behavior with non-linear nature of I–V curve of PANI/ZnO heterostructure device. The typical ohmic behavior was observed by the I–V characterization of PANI/ZnO heterostructure at the interface of PANI and ZnO thin film layer without top Pt thin layer contact. 相似文献
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Let M be a symplectic symmetric space, and let ?:M→V be an extrinsic symplectic symmetric immersion in the sense of Krantz and Schwachhöfer (2010) [7], i.e., (V,Ω) is a symplectic vector space and ? is an injective symplectic immersion such that for each point p∈M, the geodesic symmetry in p is compatible with the reflection in the affine normal space at ?(p). 相似文献
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In [L. Lebtahi, Lie algebra on the transverse bundle of a decreasing family of foliations, J. Geom. Phys. 60 (2010), 122–133], we defined the transverse bundle Vk to a decreasing family of k foliations Fi on a manifold M. We have shown that there exists a (1,1) tensor J of Vk such that Jk≠0, Jk+1=0 and we defined by LJ(Vk) the Lie Algebra of vector fields X on Vk such that, for each vector field Y on Vk, [X,JY]=J[X,Y]. 相似文献
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Local anodization on a permalloy (Ni80Fe20) thin film by an atomic force microscope (AFM) in air was studied. Fabrication of uniform structure on the permalloy film was difficult in comparison with that on a Si(1 0 0) substrate. On the permalloy film, threshold voltage for the AFM anodization increased until 3 h after exposure to air. With passage of time, I–V curves on the permalloy film also changed from metallic behavior to insulating one. In addition, I–V curves varied at positions on the permalloy film. The oxide layer with time- and position-dependencies can induce non-uniform structure in AFM anodization. However, uniformity of structure was able to be improved by using method of fabrication of dots. 相似文献
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We consider a Schrödinger-type differential expression HV=∇∗∇+V, where ∇ is a Hermitian connection on a Hermitian vector bundle E over a complete Riemannian manifold (M,g) with metric g and positive smooth measure dμ, and V is a locally integrable section of the bundle of endomorphisms of E. We give a sufficient condition for m-accretivity of a realization of HV in L2(E). 相似文献
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Intertwining operators for infinite-dimensional representations of the Sklyanin algebra with spins ? and −?−1 are constructed using the technique of intertwining vectors for elliptic L-operator. They are expressed in terms of elliptic hypergeometric series with operator argument. The intertwining operators obtained (W-operators) serve as building blocks for the elliptic R-matrix which intertwines tensor product of two L-operators taken in infinite-dimensional representations of the Sklyanin algebra with arbitrary spin. The Yang–Baxter equation for this R-matrix follows from simpler equations of the star–triangle type for the W-operators. A natural graphic representation of the objects and equations involved in the construction is used. 相似文献
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We present explicit constructions of complete Ricci-flat Kähler metrics that are asymptotic to cones over non-regular Sasaki–Einstein manifolds. The metrics are constructed from a complete Kähler–Einstein manifold (V,gV) of positive Ricci curvature and admit a Hamiltonian two-form of order two. We obtain Ricci-flat Kähler metrics on the total spaces of (i) holomorphic C2/Zp orbifold fibrations over V, (ii) holomorphic orbifold fibrations over weighted projective spaces WCP1, with generic fibres being the canonical complex cone over V, and (iii) the canonical orbifold line bundle over a family of Fano orbifolds. As special cases, we also obtain smooth complete Ricci-flat Kähler metrics on the total spaces of (a) rank two holomorphic vector bundles over V, and (b) the canonical line bundle over a family of geometrically ruled Fano manifolds with base V. When V=CP1 our results give Ricci-flat Kähler orbifold metrics on various toric partial resolutions of the cone over the Sasaki–Einstein manifolds Yp,q. 相似文献
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Let X be a smooth complex projective curve and S⊂X a finite subset. We show that an orthogonal or symplectic parabolic Higgs bundle on X with parabolic structure over S admits a Hermitian–Einstein connection if and only if it is polystable. 相似文献
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We discuss the well-known three-centre cation–anion–cation model for superexchange in insulating transition-metal compounds using limiting expansions for the Anderson–Hubbard model. We find that due to the interfering energy scales in the model, a limiting expression for the superexchange J for the idealized Mott–Hubbard (M–H) case t?U?Δ cannot be formally defined. We further show that the decomposition of the superexchange into range-dependent components is formally invalid. The well-known t4 superexchange expression, obtained from path-dependent series expansions, is not unique to these systems as it can also be obtained with many other different expansions, in which either the d–p energy difference Δ or the d-electron correlation U can actually be small. Particularly for milder relationships between the parameters, i.e. t?U?Δ, the reverse from the usual form of the series expansions can yield better agreement with the exact results. This implies that the fitting of experimental data to the simple expressions derived from path-dependent series expansions can lead to qualitatively incorrect relationships between the parameters, fictitiously within the M–H regime. 相似文献
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The random-crystal field spin-1 Blume–Capel model is investigated by the lowest approximation of the cluster-variation method which is identical to the mean-field approximation. The crystal field is either turned on randomly with probability p or turned off with q=1−p in a bimodal distribution. Then the phase diagrams are constructed on the crystal field (Δ)–temperature (kT/J) planes for given values of p and on the (kT/J,p) planes for given Δ by studying the thermal variations of the order parameters. In the latter, we only present the second-order phase transition lines, because of the existence of irregular wiggly phase transitions which are not good enough to construct lines. In addition to these phase transitions, the model also yields tricritical points for all values of p and the reentrant behavior at lower p values. 相似文献
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Current experimental data indicate that two unitarity triangles of the CKM quark mixing matrix V are almost the right triangles with α≈90°. We highlight a very suggestive parametrization of V and show that its CP-violating phase ? is nearly equal to α (i.e., ?−α≈1.1°). Both ? and α are stable against the renormalizaton-group evolution from the electroweak scale MZ to a superhigh energy scale MX or vice versa, and thus it is impossible to obtain α=90° at MZ from ?=90° at MX. We conjecture that there might also exist a maximal CP-violating phase φ≈90° in the MNS lepton mixing matrix U. The approximate quark–lepton complementarity relations, which hold in the standard parametrizations of V and U, can also hold in our particular parametrizations of V and U simply due to the smallness of |Vub| and |Ve3|. 相似文献