The dynamic processes in the surface layers of metals subjected activity of a pulsing laser irradiation, which destroyed not the crystalline structure in details surveyed. The procedure of calculation of a dislocation density generated in bulk of metal during the relaxation processes and at repeated pulse laser action is presented. The results of evaluations coincide with high accuracy with transmission electron microscopy dates. The dislocationinterstitial mechanism of laser-stimulated mass transfer in real crystals is presented on the basis of the ideas of the interaction of structure defects in dynamically deforming medium. The good compliance of theoretical and experimental results approves a defining role of the presented mechanism of mass transfer at pulse laser action on metals. The possible implementation this dislocation-interstitial mechanism of mass transfer in metals to other cases of pulsing influences is justified 1

We study the electrophysical properties of the Fe/MgO/Fe magnetic tunnel junctions (MTJ) with impurities. Sample structures are fabricated on top of fine-crystalline glass-ceramic substrates by e-beam evaporation in a relatively low vacuum ($10 À4 Torr). The influence of the first magnetic layer fabrication conditions on the degradation of the MTJ is explained by the interlayer diffusion. Various models of electrophysical processes in MTJ on polycrystalline substrates are discussed. The current-voltage (I-V) characteristics of the fabricated structures are found to exhibit a region with negative differential resistance, similar to the one in tunneling diodes. We explain this phenomenon by the formation of excitons in the MgO layer modified by the conductive impurity atoms and their diffusion. The obtained results will be useful in the development of MRAM devices containing MTJs and tunneling diodes.

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The influence of moving dislocations on mass-transfer and the phenomena, accompanying it in pulse-deformed metals is studied in a real-time. Transport of self-interstitial atoms (SIAs) by mobile edge dislocations in crystal with FCC lattice is investigated by molecular dynamics. A strain rate (106s-1) and dislocation density (1010– 1012cm-2) in simulated crystal corresponds to a laser effect in a Q-factor mode. The experimental investigations in a real-time are performed by recording of electrical signal induced by the laser pulse irradiation of metal foils of different crystal structures.

Mass transfer in iron and nickel stimulated by pulsed laser radiation is studied by the radioactive isotope method. New experimental results are obtained and an analysis in terms of kinetic equat.ions is given. It is shown: (a) exposure of the metal surface to high intensity pulsed laser radiation leads to an accelerated atomic migration into the sample; (b) an effective retardation, the value of which depends upon the presence of crystalline defects in metals has an esaential influence on the atomic migration rate stimulated by the laser; (c) multiple laser loading results in a concentration maximum formed inside the sample, the depth displacement of which depends upon the energy of light flux and the number of pulsed loadings.