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Within the model of self-consistent connection of quasi-Rayleigh wave with adsorbed atoms, a method of constructing a new class of radiometric sensors of the temperature and concentration of adsorbed atoms on the surface acoustic waves is proposed. Based on the developed theoryofthe dispersion and acoustic mode width of a quasi-Rayleigh waveon theadsorbed surface of monocrystals with a Zincblendestructure, the temperature coefficient of the resonant frequency of the surface acoustic wave is calculated depending on the temperature and on the concentration of adsorbed atoms. [ABSTRACT FROM AUTHOR]

In the paper, the effect of the electric field on the conditions of formation and on the period of the surface superlattice of adatoms in n-GaAs semiconductor is investigated. It is established that in GaAs semiconductor, an increase in the electric field strength, depending on the direction, leads to an increase or decrease of the critical temperature (the critical concentration of adatoms), at which the formation of self-organized nanostructure is possible. It is shown that in strongly alloyed n-GaAs semiconductor, an increase of the electric field strength leads to a monotonous change (decrease or increase depending on the direction of the electric field) of the period of self-organized surface nanostructures of adatoms. [ABSTRACT FROM AUTHOR]

Dispersion relations for the spectra of surface electron states on a dynamically deformed adsorbed surface of a monocrystal with the Zinc blende structure are received. It is established that the dependences of the band gap width and of the concentration of electrons on the concentration of adatoms N0d upon the solid surface are of nonmonotonous character. [ABSTRACT FROM AUTHOR]

The dispersion law of elastic surface acoustic waves and the energy width of the surface acoustic mode are found to the long-wave approximation depending on the concentration of the adsorbed atoms and the deformation potential of the adatom. The mirror image forces and the nonlocal elastic interaction between the adsorbed atom and the matrix atoms are taken into consideration. [ABSTRACT FROM AUTHOR]

Magnetoresistance as a tool of basic parameters determination of minority charge carriers and the ratio of minority charge carriers conductivity to majority ones in solid matter has been considered within the framework of the phenomenological two-band model. The criterion of the application of this model has been found. As examples of these equations usage the conductor, semiconductor and superconductor have been introduced. From the obtained temperature dependences of the aforementioned values in superconductor, a supposition of a deciding role of minority charge carriers in the emergence of superconductivity state has been made. [ABSTRACT FROM AUTHOR]

Within nonlocal elastic interaction between an adsorbed atom and matrix atoms and in consideration of the mirror image forces, a dispersion law of elastic surface acoustic waves is found to the long-wavelength approximation depending on the concentration of adsorbed atoms and the deformation potential of the adatom. The energy width of the surface acoustic mode is calculated depending on the concentration of adsorbed atoms. [ABSTRACT FROM AUTHOR]

The theory of nucleation of nanoscale structures of the adsorbed atoms (adatoms), which occurs as a result of the self-consistent interaction of adatoms with the surface acoustic wave and electronic subsystem is developed. Temperature regimes of formation of nanoclusters on n-GaAs surface under the action of laser irradiation are investigated. The offered model permits to choose optimal technological parameters (temperature, doping degree, intensity of laser irradiation) for the formation of the surface periodic defect-deformation structures under the action of laser irradiation. [ABSTRACT FROM AUTHOR]

The model of spatial-temporal distribution of point defects in a three-layer stressed nanoheterosystem GaAs/InxGa1-xAs/GaAs considering the self-assembled deformation-diffusion interaction is constructed. Within the framework of this model, the profile of spatial-temporal distribution of vacancies (interstitial atoms) in the stressed nanoheterosystem GaAs/InxGa1-xAs/GaAs is calculated. It is shown that in the case of a stationary state (t>5τd(2)), the concentration of vacancies in the inhomogeneously compressed interlayer is smaller relative to the initial average value Nd0(2) by 16%. [ABSTRACT FROM AUTHOR]

Non-linear theory of diffusion of impurities in porous materials upon ultrasonic treatment is described. It is shown that at a defined value of deformation amplitude, an average concentration of vacancies and temperature as a result of the effect of ultrasound possibly leads to the formation of nanoclusters of vacancies and to their periodic educations in porous materials. It is shown that at a temperature smaller than some critical value, a significant growth of a diffusion coeWcient is observed in porous materials. [ABSTRACT FROM AUTHOR]

The mechanic-deformation model of a nanoheterosystem with quantum dots which is under the influence of an acoustic wave is constructed. The uniform deformation of the InAs/GaAs heterostructure with InAs quantum dots is calculated. The offered approach takes into account as a strain caused by a misfit of parameters of lattices of contacting materials as well as the influence of an acoustic wave on the intense state of a heterosystem with quantum dots [ABSTRACT FROM AUTHOR]

A theoretical research is presented concerning the potential distribution and electric field intensity in the InAs/GaAs nanoheterosystem with InAs QDs within the framework of self-consistent electron-deformation model. It is shown that at the strained border between a quantum dot and matrix there is a double electric layer, that is n+ - n junction. [ABSTRACT FROM AUTHOR]

Analytical expressions describing the energy spectrum of electrons and holes are obtained for a quantum dot (QD) occurring in a self-consistent strain field created by an array of coherently stressed QDs. A method of taking into account the lattice mismatch at the QD–matrix interface is proposed that allows for the dependence of the mismatch parameter on the QD size and the matrix layer thickness. It is shown that the internal elastic strain arising at the QD–matrix interface influences the energy spectrum of electrons more significantly than the spectrum of holes. © 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]

In the framework of an electron-deformation model, a mechanism of electron-deformation dipole formation at a strained heterointerface was considered. For a ZnSe/ZnS heterostructure, an external electric field ∼120 kV/cm normal to the heterointerface brought about an additional compression strain of ∼4% (∼3%) in the ZnSe (ZnS) lattice. For an opposite field direction, a tensile strain of ∼5% (∼5%) was observed. [ABSTRACT FROM AUTHOR]

The model of self-consistent electron-deformation coupling was used to show that additional periodic local electron-deformation wells and barriers arise in the vicinity of heterocontact in a strained ZnSe/ZnS superlattice within the main quantum well (ZnSe) and above the main barrier (ZnS). It is found that, for the thickness of the ZnSe overgrown layer in the range from 10 to 20 Å, the electron ground-state energy E[sub 0c] decreases steadily with increasing conduction-electron concentration n[sub c]; however, for the layer thickness exceeding 20 Å, the concentration dependence E[sub 0c] = f(n[sub c]) becomes nonmonotonic and features a maximum, which shifts to lower concentrations n[sub c] as the layer thickness increases. [ABSTRACT FROM AUTHOR]

This paper is devoted to a self-consistent solution of the electron-strain interaction in a crystal with linear dislocations. It shows that such self-consistency causes charge to be redistributed in the neighborhood of the dislocation nucleus and hence renormalizes the strain caused by the dislocation. The resulting charge redistribution forms a dipole whose moment is proportional to the length of the dislocation. The dislocation kinetics in the crystal can be affected when an external dynamic or static electric field acts on such a dipole. [ABSTRACT FROM AUTHOR]

In the context of the deformation potential model, baric dependences of the energy structure of InAs quantum dots in a GaAs matrix are calculated. Under the assumption of the absence of interaction between the spherical quantum dots of identical sizes, the energy dependence of the baric coefficient of energy of the radiative transition in the quantum dot is determined. A similar dependence is also found experimentally in the photoluminescence spectra under uniform compression of the InAs/GaAs structures. Qualitative agreement between the theory and experiment as well as possible causes for their quantitative difference are discussed. It is concluded that such factors as the size dispersion, Coulomb interaction of charge carriers, and tunnel interaction of quantum dots contribute to this difference. [ABSTRACT FROM AUTHOR]