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51.
High dose implantations of Fe into metals and semiconductors have been performed with beam energies up to 1 MeV at the UNILAC-injector at GSI. Unusual high concentrations of 70 atomic % for Si and 20 atomic % for Cu have been obtained, with doses of 1018 Fe/cm2 in the case of Si and several 1017 Fe/cm2 in the case of Cu. For Si the thickness of the layers were determined by Rutherford backscattering to be 4500 Å. These results are consistent with calculations, which show that these high concentrations are due to the reduction of the sputter yield at the relative high particle energies. Samples have been characterized using several complementary methods (Mössbauer Spectroscopy (MS), Rutherford Backscattering Spectroscopy (RBS), Auger electron Spectroscopy (AES). Scanning Electron Microscopy (SEM), X-ray diffraction (XRD)). 相似文献
52.
53.
We develop the quantization of topological solitons (vortices) in three-dimensional quantum field theory, in terms of the Euclidean region functional integral. We analyze in some detail the vortices of the abelian Higgs model. If a Chern-Simons term is added to the action, the vortices turn out to be anyons, i.e. particles with arbitrary real spin and intermediate () statistics. Localization properties of the interpolating field, scattering theory and spin-statistics connection of anyons are discussed. Such analysis might be relevant in connection with the fractional quantum Hall effect and two-dimensional models of HighT
csuperconductors. 相似文献
54.
During ageing the Al-2·0 at. %Zn-1·0 at. % Mg alloy at elevated temperatures the width of the precipitation free zone (PFZ) at both sides of the grain boundaries (GB) is identical with that free of quenched-in dislocation loops (DL). After sufficiently long ageing a band of precipitates is growing inside the former PFZ and the DLs in the midgrain regions act as sites for the heterogeneous nucleation of the-phase. Two precipitation processes significantly affect the mechanical properties. TEM correlates grain boundary precipitate density and morphology with grain boundary misorientation. 相似文献
55.
56.
Claudio Albanese Jürg Fröhlich Thomas Spencer 《Communications in Mathematical Physics》1988,119(4):677-699
This is our second paper devoted to the study of some non-linear Schrödinger equations with random potential. We study the non-linear eigenvalue problems corresponding to these equations. We exhibit a countable family of eigenfunctions corresponding to simple eigenvalues densely embedded in the band tails. Contrary to our results in the first paper, the results established in the present paper hold for an arbitrary strength of the non-linear (cubic) term in the non-linear Schrödinger equation. 相似文献
57.
58.
The dynamic susceptibility () measured between 10 Hz and 10 MHz on different GdCl3-ellipsoids (T
c=2.21 K) reveals a completely reversible motion of the domain walls. Taking into account the contribution of the fast adiabatic intradomain magnetization to the nearly Debye-shaped (), we determine for the first time the kinetic Onsager coefficientL
d of the domain wall relaxation of a ferromagnet. Approaching the CurietemperatureL
d speeds up critically, which by a novel simple relaxational model can be related to the increasing width (=correlation length) of linear Bulaevskii-Ginzburg domain-walls and to the shrinking domain period. The reduction ofL
d by an external field can be represented by a universal scaling function, and within the same dynamical model, this effect is ascribed to the increase of the domain period, predicted for a bubble phase. However, the effect of sample size onL
d is much smaller than expected. 相似文献
59.
60.
Analysis of K-shell excitation spectra of gas-phase molecules containing at least two atoms of either B, C. N. O or F reveals the existence of a striking correlation between the bond length of the atomic pair. the sum of their atomic numbers and the associated α-shape resonance energy. Empirical rules are established which allow the derivation of intramolecular distances with accuracies reliably better than ± 0.05 A from the K-.shell absorption spectrum of one of the atoms in the Molecule. 相似文献