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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.

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.

A significant carbon diffusion mobility acceleration as a result of cyclic γ↔ε martensitic transformations in iron-manganese alloy is determined by one- and two-dimensional structure defects of ε-martensite with face-centered close-packed lattice. Such defects (dislocations, low angle sub-boundaries of dislocations, chaotic stacking faults) were formed during cyclic γ↔ε martensitic transformations. Peak carbon diffusion coefficient increase was observed under thermocycling when maximum quantity of lattice defects increase was fixed.

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