We report a study of the electron tunneling transport in point-contact junctions formed by a sharp Ag tip and two different highly correlated oxides, namely, a magnetoresistive manganite La 0.66 Ca 0.34 MnO 3 and a superconducting cuprate LaBa 2 Cu 3 O 7-x . Strong chemical modifications of the oxide surface (supposedly, oxygen ion displacements) caused by applying high voltages to the junctions have been observed. This effect is believed to be responsible for an enormous growth of inelastic tunneling processes across a transition region that reveals itself in an overall «V»-shaped conductance background, with a strong temperature impact. The mechanism of the inelastic scattering is ascribed to charge transmission across magnetically active interfaces between two electrodes forming the junction. To support the latter statement, we have fabricated planar junctions between Cr and Ag films with an antiferromagnetic chromium oxide Cr 2 O 3 as a potential barrier and at high-bias voltages have found an identical conductance trend with a similar temperature effect.

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Giant growth of the differential resistance has been observed in a tunnel junction consisting of superconducting lead with Heusler’s ferromagnetic alloy Co2CrAl for low bias voltages. This effect is attributed to the appearance of a nonequilibrium state in the lead film as a result of spin injection into the superconductor.

A study of the density of quasiparticle states of a lead film, which is a conventional superconductor with spin-singlet electron pairing, as a function of the nanoscale ferromagnetic nickel layer thickness that is in direct contact with the lead (inverse proximity effect). It is found that the penetration depth of superconducting correlations into the ferromagnetic nickel is of the same order of magnitude as in contacts involving lead and a normal metal. This behavior can be explained by the appearance of an inhomogeneous exchange field at the interface, which leads to the effective conversion of spin-singlet (rapidly decaying in a ferromagnet) Cooper pairs into spin-triplet pairs, which are stable with respect to exchange interaction.

The features of the physical mechanisms of controlled ion-plasma formation of the new functional nanomaterials are investigated. The technological regimes of formation of functional nanostructured materials under combined impact of several plasma sources are investigated; the structural and electrical properties of the obtained TiN films are studied. The structures of films are studied with scanning tunnelling microscope JSPM-4500/4610 interlocked with an atomic force microscope. As shown, the optimized helicon-arc reactor demonstrates the unique properties and provides controlled lowtemperature formation of the dense regular TiN nanostructures with the sizes from a few to tens of nanometres.Вивчено особливості фізичних механізмів керованого йонно-плазмового формування нових функціональних наноматеріялів. Відпрацьовано тех-нологічні режими формування функціональних наноструктурованих ма-теріялів за спільної роботи кількох джерел плазми; вивчено структурні та електрофізичні особливості одержаних плівок TiN. Структури плівок до-сліджено на сканівному тунельному мікроскопі JSPM-4500/4610, збло-кованому з атомним силовим мікроскопом. Встановлено, що оптимізова-ний гелікон-дуговий реактор демонструє унікальні властивості і забезпе-чує кероване низькотемпературне формування щільних упорядкованих наноструктур TiN з розмірами від одиниць до десятків нанометрів.Изучены особенности физических механизмов управляемого ионно-плазменного формирования новых функциональных наноматериалов. Отработаны технологические режимы формирования функциональных наноструктурированных материалов при совместной работе нескольких источников плазмы; изучены структурные и электрофизические особен-