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991.
The states of electron-hole pairs in spherical silicon nanocrystals are theoretically studied using the “multiband” effective-mass approximation in the limit of an infinitely high potential barrier at the boundary. The degeneracy of the states at the top of the valence band is taken into account in the spherical approximation, and the ellipsoidal character of the electronic spectrum in the conduction band is allowed for. Coulomb interaction-induced corrections to the energy of an electron-hole pair are found. 相似文献
992.
993.
For either of the two reflection spectra of cadmium difluoride that are known from experiments, a complete set of the fundamental
optical functions is calculated in the energy range 4–45 eV with the Kramers-Kronig relationships. The basic features of the
optical spectra are established, and a hypothesis for their origin is suggested based on the known theoretical results for
the band structure. 相似文献
994.
Amorphous silver, copper, gold, and iron films of a thickness between 6 and 350 nm are grown on polymeric substrates by vacuum
evaporation. The nanostructure of the films is investigated. The dependence of the conductivity on the film thickness is obtained,
and a correlation between the surface morphology and the conductivity is established. 相似文献
995.
The integral characteristics of magnetization switching in amorphous gadolinium-cobalt films with perpendicular anisotropy
are studied by visualizing the domain structure and measuring magnetooptic hysteresis loops. The films have a radial gradient
of magnetic properties that is due to a spatially nonuniform thermal field. Magnetization switching in those film areas where
the domain wall motion depends only on the coercive force is simulated in simple terms. In a first approximation, local events
of magnetization switching are shown to take place independently of each other and the net hysteresis loop can be represented
as a sum of the local loops. 相似文献
996.
O. V. Shramkova 《Technical Physics》2004,49(2):232-237
Magnetoplasma waves and inhomogeneous (complex) waves in an infinite semiconductor superlattice in a magnetic field are studied, and dispersion curves are obtained. It is shown analytically and numerically that, in periodic structures, among inhomogeneous waves, there are many complex waves for which the imaginary part of the wave vector is greater than the real part. The effect of dissipation in a medium on the dispersion curves of magnetoplasma waves is examined. The dependence of the minimum phase velocity on the collision frequency and the magnetic field strength is studied. 相似文献
997.
An analytical expression for the concentration profile of a low-soluble diffusant in a sample is derived for a high-capacity
diffusion source. The model is checked by determining the diffusion coefficient of yttrium in beryllium. 相似文献
998.
R. G. Zakinyan 《Technical Physics》2004,49(9):1110-1115
The motion of the front of crystallization and the growth of a film at the surface of a plate are analyzed in the case of
a laminar and in the case of a turbulent flow mode. Conditions are determined under which there occurs a transition from a
matt inhomogeneous structure to a transparent homogeneous structure of ice. It is shown that, for a film to be steadily preserved
at the plate surface, the film thickness must be larger than a critical equilibrium-thickness value h
b.c, in which case a transparent homogeneous structure of ice is formed. Otherwise, the film at the plate surface is unstable
and disappears in the course of time. The icing of aircrafts is the most important application of the results obtained in
this study. 相似文献
999.
Influence of the skin effect on the absorption of electromagnetic radiation by a fine metal particle
The cross section of absorption of electromagnetic radiation by a fine spherical metal particle is calculated. The influence of the skin effect on the absorption cross-section is estimated for an arbitrary ratio between the free path and size of the particle. The results of this work are compared with those obtained earlier in the framework of classical electrodynamics. It is shown that taking into account the kinetic effects modifies essentially the known data for the skin effect in a spherical particle. 相似文献
1000.
E. L. Pankratov 《Technical Physics》2004,49(1):114-118
The establishment of the steady-state dopant profile in a medium with a time-variable diffusion coefficient is considered
within the approach proposed previously for estimating mass-and heat-transfer time characteristics. It is shown that the time
it takes for the equilibrium concentration to set in may be increased or decreased by appropriately choosing the law of variation
of the diffusion coefficient. 相似文献