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991.
P. Dimopoulos K. Farakos S. Nicolis 《The European Physical Journal C - Particles and Fields》2002,24(2):287-296
We explore the phase diagram of the five-dimensional anisotropic Abelian Higgs model by Monte Carlo simulations. In particular,
we study the transition between the confining phase and the four-dimensional layered Higgs phase. We find that, in a certain
region of the lattice parameter space, this transition can be first order, and that each layer moves into the Higgs phase
independently of the others (decoupling of layers). As the Higgs couplings vary, we find, using mean field techniques, that
this transition may probably become second order.
Received: 21 December 2001 / Published online: 12 April 2002 相似文献
992.
Bulanyi M. F. Gorban' A. A. Kovalenko A. V. Polezhaev B. A. Prokof'ev T. A. Khmelenko O. V. 《Russian Physics Journal》2002,45(12):1215-1219
The photoluminescence spectra of ZnS : Mn plastically deformed single crystals are investigated. It is established that the plastic strain causes the relative concentrations of individual manganese emission centers to change together with conditions of excitation of the centers whose nearest environment has been rearranged upon plastic strain. 相似文献
993.
K. P. Meletov M. P. Kulakov N. N. Kolesnikov J. Arvanitidis G. A. Kourouklis 《JETP Letters》2002,75(8):406-409
Raman spectra of MgB2 ceramic samples were measured as a function of pressure up to 32 GPa at room temperature. The spectrum at normal conditions contains a very broad peak at ∼590 cm−1 related to the E 2g phonon mode. The frequency of this mode exhibits a strong linear dependence in the pressure region from 5 to 18 GPa, whereas, beyond this region, the slope of the pressure-induced frequency shift is reduced by about a factor of two. The pressure dependence of the phonon mode up to ∼5 GPa exhibits a change in the slope, as well as a “hysteresis” effect in the frequency vs. pressure behavior. These singularities in the E 2g mode behavior under pressure support the suggestion that MgB2 may undergo a pressure-induced topological electronic transition. 相似文献
994.
N.P. Somasiri W.K. Toh X. Chen I.D. Robertson A.A. Rezazadeh 《International Journal of Infrared and Millimeter Waves》2002,23(12):1777-1785
This paper describes numerical modelling of a dual band multi-layered microstrip patch antenna operating at 35GHz on an in-house semi-insulating GaAs substrate. The simulated and measured resonant frequencies at both lower and upper resonant frequencies will be compared to check the accuracy of the different numerical modelling techniques. 相似文献
995.
A cooperative defect-deformation (DD) mechanism is developed for the nucleation of the quasi-monodisperse ensemble of nanoparticles in the low-temperature deposition of Ga atoms in the presence of laser radiation. A comparison with experiment is carried out, and a good agreement between the theoretical and experimental results has been obtained. In particular, in accordance with the DD model, it has been found that the arrangement of nanoparticles is characterized by a latent hexagonal order, and their shape is quasi-hexagonal. It has been shown that the characteristics of the deposited ensemble of nanoparticles can be controlled with the use of an anisotropic deformation. 相似文献
996.
997.
The asymptotic value of the melting entropy, i.e. ΔSf = R ln 2 for vanishing relative change of volume on melting, can be derived from the vibrational entropy due to vibrating dislocations, which are introduced into a material on melting. 相似文献
998.
999.
Translated from Programmnoe Oborudovanie i Voprosy Prinyatiya Reshenii, pp. 152–184, 1989. 相似文献
1000.
V. K. Mel'nikov 《Communications in Mathematical Physics》1991,137(2):359-381
It is shown that the nonlinear Schroedinger equation with a self-consistent source admits investigation by the inverse scattering method for the Dirac operator. The conditions are found under which the solutions of the nonlinear Schroedinger equation with a self-consistent source describe the creation and annihilation of solitons. 相似文献