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101.
A. G. Milekhin A. I. Nikiforov M. Yu. Ladanov O. P. Pchelyakov S. Schulze D. R. T. Zahn 《Physics of the Solid State》2004,46(1):92-96
This paper reports on the results of resonant Raman scattering investigations of the fundamental vibrations in Ge/Si structures with strained and relaxed germanium quantum dots. Self-assembled strained Ge/Si quantum dots are grown by molecular-beam epitaxy on Si(001) substrates. An ultrathin SiO2 layer is grown prior to the deposition of a germanium layer with the aim of forming relaxed germanium quantum dots. The use of resonant Raman scattering (selective with respect to quantum dot size) made it possible to assign unambiguously the line observed in the vicinity of 300 cm?1 to optical phonons confined in relaxed germanium quantum dots. The influence of confinement effects and mechanical stresses on the vibrational spectra of the structures with germanium quantum dots is analyzed. 相似文献
102.
O. P. Bobrov S. N. Laptev H. Neuhäuser V. A. Khonik K. Csach 《Physics of the Solid State》2004,46(10):1863-1867
Isochronous relaxation of tensile stresses is measured in a bulk Pd40Cu30Ni10P20 metallic glass in the initial state and after certain thermal treatments. The results of measurements are used to find the energy spectrum of irreversible structural relaxation, from which the temperature dependence of shear viscosity is then calculated. This dependence is also found independently from measurements of creep in the same glass. The calculated viscosity is shown to agree well with the experimental data. 相似文献
103.
O. Yu. Borkovskaya N. L. Dmitruk I. B. Ermolovich R. V. Konakova V. V. Milenin 《Technical Physics》2004,49(3):325-329
The properties of nonrectifying AuGe/GaAs (Al0.4Ga0.6As) contacts exposed to heat treatment, 60Co γ radiation, and γ radiation combined with the application of an electrical bias are studied. A correlation between the
type of interfacial interaction in the contacts and their resistance is found. Results obtained are explained in terms of
a diffusion model with a movable boundary of the metal layer. 相似文献
104.
O. I. Kotov L. B. Liokumovich S. I. Markov A. V. Medvedev A. V. Khlybov 《Technical Physics》2004,49(1):71-75
Mechanisms of polarization modulation in a single-mode fiber that modulate the phase difference between polarization modes without affecting their amplitudes are considered. A coefficient that characterizes the efficiency of cylindrical piezoceramic modulators and is independent of their resonant properties is introduced. Analytical expressions for this coefficient for different modulation mechanisms are derived. The lateral pressure on the fiber is shown to provide the highest efficiency. For isotropic fibers, a modulator with a squeezing covering, which increases significantly its efficiency, is studied. For anisotropic fibers, the most appropriate way of phase difference modulation is longitudinal extension, in which case the birefringence axes do not have to be matched. In most cases, the measured and predicted efficiencies are in good correspondence. 相似文献
105.
106.
107.
108.
The kinetics of current decay and partial restoration in planar doped GaAs:Si due to the formation of DX? centers in strong electric fields has been experimentally studied. The existence of thresholds with respect to the field strength and donor concentration is explained. A model of the DX? center formation is proposed, which is based on the notions about variation of the depth and width of a potential well created by planar doping, caused by the redistribution of hot electrons between quantum confinement subbands. As a result, the energy level of DX? centers, which is situated above the potential well depth in the absence of strong field, decreases and falls within the potential well. This makes possible the DX? center formation, provided that hot electrons, occupying the resonance electron levels in the conduction band, simultaneously excite local vibrational modes. 相似文献
109.
Results of a numerical analysis of mass transfer in systems of macroscopic particles with various isotropic interaction potentials are presented. Parameters that determine transport properties of nonideal dissipative systems are obtained for a broad class of model potentials. An approximate expression for the diffusivity of interacting particles is proposed. The relationship between diffusivity and viscosity is analyzed for strongly nonideal systems. 相似文献
110.
Yu. B. Bolkhovityanov S. Ts. Krivoshchapov A. I. Nikiforov B. Z. Ol’shanetskii O. P. Pchelyakov L. V. Sokolov S. A. Teys 《Physics of the Solid State》2004,46(1):64-66
Different techniques for the fabrication of structures containing ensembles of ultrasmall germanium nanoclusters distributed with a high density over the substrate surface are discussed. How to control the morphology and ordering of these ensembles is also discussed. 相似文献