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101.
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105.
Let G be a compact Lie group acting on a compact manifold M. In this article, we associate to a G-transversally elliptic symbol on M a G-invariant generalized function on G, constructed in terms of equivariant closed differential forms on the cotangent bundle T
*
M.
Oblatum 24-VII-1995 相似文献
106.
107.
Tristan Rivière 《Letters in Mathematical Physics》1998,45(3):229-238
We introduce a formulation of the Skyrme problem using differential forms. By means of this formulation, we prove first that the homothetic map between the standard three-sphere of radius R, S3
r R4, and S3
1 is the unique minimizer, modulo isometries, of the Skyrme energy in its homotopy class, for any R less than some critical value R0 (3/2, 2]. We then establish a stability result for this Skyrme-form problem from which we can recover the result of M. Loss and N. S. Manton which states that this homothetic map is stable only up to R = 2. 相似文献
108.
M. Morcrette A. Gutiérrez-Llorente A. Laurent J. Perrière P. Barboux J.P. Boilot O. Raymond T. Brousse 《Applied Physics A: Materials Science & Processing》1998,67(4):425-428
x La2/3+yTiO3-δ perovskite (with δ≤0.5) were deposited by the laser ablation technique from Li0.33La0.56TiO3 targets. Their growth onto MgO substrateswas studied as a function of the oxygen pressure. For films grown in vacuum (10-6 mbar), a La0.63TiO2.5 composition was obtained, meaning that Ti3+ alone is present in the films, while Li ions are not incorporated under these conditions. This material shows good electric
conductivity (ρ=500 mΩ cm). By contrast, insulating films with a Li0.1La0.70TiO3 composition corresponding to the Ti4+ species were obtained at high oxygen pressures (>0.05 mbar). For all conditions, textured films were grown with different
orientations depending on the temperature and the oxygen pressure.
Received: 10 September 1997/Accepted: 24 November 1997 相似文献
109.
J. Torrès T. Martin 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,12(3):319-322
In the light of the recent analogs of the Hanbury-Brown and Twiss experiments [1] in mesoscopic beam splitters, negative current
noise correlations are recalled to be the consequence of an exclusion principle. Here, positive (bosonic) correlations are
shown to exist in a fermionic system, composed of a superconductor connected to two normal reservoirs. In the Andreev regime,
the correlations can either be positive or negative depending on the reflection coefficient of the beam splitter. For biases
beyond the gap, the transmission of quasiparticles favors fermionic correlations. The presence of disorder enhances positive
noise correlations. Potential experimental applications are discussed.
Received 1 June 1999 相似文献
110.
S. Hagège 《Interface Science》1999,7(2):85-101
Small inclusions of lead have been embedded in pure silicon by rapid quenching. They are topotactic-truncated octahedra with a smaller aspect ratio than the ones found in aluminum. They appear also on single and multiple twins as a bicrystalline unit with a compound morphology. No overheating has been detected, while undercooling is size dependent and can reach 80 K. These results are compared to the structure, morphology and thermal behavior of lead inclusions in aluminum and other cubic matrices. 相似文献