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991.
M.W.C. Dharma-wardana A.H. MacDonald G.C. Aers D.J. Lockwood W.T. Moore R.L.S. Devine 《Superlattices and Microstructures》1987,3(6)
Results of Raman scattering experiments on (a) periodic superlattices made up of GaAs/InxGa1−xAs layers with high indium concentrations, (b) GaAs/Ga1−xAlxAs Fibonacci superlattices, are presented. We discuss the observed peak positions and intensities using the continuum theory of acoustic wave propagation in layered media and the photo-elastic coupling model. 相似文献
992.
993.
Y. Zhang T. M. Benson P. Sewell A. Vukovic D. Zhang W. J. Pan A Loni D. Furniss A. B. Seddon 《Optical and Quantum Electronics》2006,38(1-3):97-110
This paper presents our recent simulation results and novel designs of single mode large cross-section glass-based waveguides for photonic integrated circuits (PICs). Simulations were performed using an in-house Finite Difference (FD) based mode solver and the FD Beam propagation Method (FD-BPM). Our simulation results show that this innovative technology could provide a simplified means to couple optical energy efficiently between optical components in a single chip. This would provide the base for the future large-scale integration of optical components in PICs. The novel idea of using single mode large cross-section glass-based waveguides as an optical integration platform is an evolutionary innovative solution for the monolithic integration of optical components, in which the glass-based structures act both as waveguides and as an optical bench for integration. This allows easy and efficient optical coupling between optical components and optical fibres, removing costly and tedious alignment problems and considerably reducing optical coupling losses in PICs. We expect that the glass-based waveguide PICs technology will enable the emergence of a new generation of compact, reliable, high speed, and multifunctional devices. 相似文献
994.
D. Chiladze J. Carbonell S. Dymov V. Glagolev M. Hartmann V. Hejny A. Kacharava I. Keshelashvili A. Khoukaz H.R. Koch V. Komarov P. Kulessa A. Kulikov G. Macharashvili Y. Maeda T. Mersmann S. Merzliakov S. Mikirtytchiants A. Mussgiller M. Nioradze H. Ohm F. Rathmann R. Schleichert H.J. Stein H. Ströher Yu. Uzikov S. Yaschenko C. Wilkin 《Physics letters. [Part B]》2006
995.
S.N. Vdovichev B.A. Gribkov S.A. Gusev E. Il’ichev Yu.N. Nozdrin G.L. Pakhomov A.V. Samokhvalov R. Stolz A.A. Fraerman 《Journal of magnetism and magnetic materials》2006
The effect of an array of ferromagnetic nanoparticles on the field-dependent critical current of the short overlap Josephson junction is experimentally studied. Large reversible variations of the maximum critical current are observed depending on the magnetic state of the particles. The pronounced commensurability effects are detected which are proved by the additional peaks of magnetic field induced diffraction pattern. 相似文献
996.
997.
In the present paper, we study the rate of convergence in simultaneous approximation for the Bézier variant of the Baskakov-Beta operators by using the decomposition technique of functions of bounded variation. 相似文献
998.
The awaited dark matter (DM) neutralino annihilation signal from the galactic halo crucially depends on the presence of small-scale
clumps. A mass function of the DM small-scale clumps is calculated in the standard cosmological scenario. The final distribution
of clumps in the Galaxy is influenced by their tidal destruction. The basic sources of clump destruction are (i) clumps of
larger scales, (ii) the gravitational field of the galactic disk, (iii) the stars in the galactic bulge, and (iv) the stars
in the galactic halo. The destruction of clumps due to their mutual tidal interactions is important at earl stages of hierarchical
clustering and the galactic halo formation. The clumps surviving through the hierarchical clustering are continuously destroyed
by interactions with the galactic disk and stars. It is shown that, among the Moon or Earth mass DM clumps surviving through
the hierarchical clustering, only 20% will further survive near the Sun’s position mainly because of the tidal destruction
by the galactic disk. This reduction of DM clump density significantly diminishes the expected DM annihilation signal from
the galactic halo.
The text was submitted by the authors in English. 相似文献
999.
The impedance spectra of Pb5Ge3O11 single crystals are measured in the frequency range from 5 Hz to 13 MHz at temperatures of 600 to 800 K in dry air and in
a dry or wet nitrogen gas. It is found that the temperature and the gas composition significantly affect the electrical properties
of the compound. The data obtained are used to discuss the origin of crystal lattice defects and their influence on charge
transfer. It is concluded that the conduction is mixed in character (p-type electronic and ionic due to oxygen ions). The proton conduction is shown experimentally to be feasible. The possible
mechanisms of proton transport in Pb5Ge3O11 are discussed. 相似文献
1000.