Comparative studies of resistive switching (RS) effect of metal/nanocomposite/metal (M/NC/M), metal/nanocomposite/LiNbO3/metal (M/NC/LNO/M) structures based on NC (Co40Fe40B20)x(LiNbO3)100-x (x=6-20 at.%) with CoFe nanogranules 2-4 nm in size, as well as structures without a NC layer (M/LNO/M), have been carried out. It was found that the percolation conductivity in NC and presence of a thin LNO layer play a key role in the RS effect. When the metal content approaches the percolation threshold of M/NC/M structures (xp~10 at.%), low-resistance percolation nanochannels of granules are formed in structures with an embedded LNO layer, which ensure their stable RS, which, however, are noticeably suppressed as x decreases relative to xp by Delta x~1-2 at.%. Keywords: resistive switching, memristor, nanocomposite, percolation.

The topological features of the formation of (Co40Fe40B20)15(LiNbO3)85 composite films deposited by ion-beam method on a metal electrode Cr/Cu/Cr has been investigated. The presence of a dielectric layer between the upper Cr layer and the CoFe-LiNbO3 film with a thickness of dox~ 15 nm has been established. The difference in the size of granules near the amorphous layer and in the volume of the film has been shown. A model of the formation of (Co40Fe40B20)x(LiNbO3)100-x nanocomposite film at the initial stage of growth has been proposed. It has been shown that the formation of α-LiNbO3 layer on the chrome metal film surface is possible with the realization of island and layer-by-layer growth mechanisms for various phases of the composite. Keywords: nanocomposite, growth mechanisms, self-organization, structure.

The optical and electrical properties of bismuth ferrite thin films obtained by high-frequency magnetron sputtering in an atmosphere of argon and oxygen (80%+20%) has been studied. Investigations of the optical properties have shown that for polycrystalline bismuth ferrite films the optical band gap is ~2.3 eV, which is in the range of given in the literature values. The dependences of the specific electrical conductivity on the magnitude of the electric field has been studied for the synthesized films. It has been established that the electrical conductivity does not depend on the electric field strength up to the value of E=2.1·106 V/m. The experimental results are discussed in terms of the model of charge carrier injection from aluminum electrode into the conduction band of bismuth ferrite. Keywords: electrical conductivity, strong electric fields, optical absorption coefficient, memristor effect.