Ab initio calculation and spectral properties of nano- and bulk materials

This paper presents the development of ab initio calculation of the electronic structure of either clusters, nano-crystals, doped and unperfected bulk crystals. In addition, analysis of selected experimental data for γ- or plasma irradiated pure and doped wide-band gap oxides such as sapphire, α-Al₂O₃, garnet, Y₃Al₅O₁₂, Gd₃Sc₂Al₃O₁₂ and perovskites YAlO₃, SrTiO₃ is presented. Change in the crystals surface morphology and spectroscopic properties of sapphire, perovskites, garnets as well as ion oxidation state in pure and doped γ- and plasma irradiated crystals are discussed in detail using the optical and X ray spectroscopy experimental results.     

Spin field emission and state switching in a magnetic tunnel junction

The phenomena of spin tunneling and spin torque transfer between magnetic layers of a tunnel spin-valve setup under weak and strong field emissions of spin-polarized electrons are considered. Bifurcational features of changes in the macrospin states under the impact of a tunnel current are discussed for varying directions of the spin-polarization vector.     

Optical properties of laser plasma produced by pulses of different duration

The results of experiments on the interaction of laser radiation pulses (at intensities of up to 1015 W cm−2) of different durations (t = 3ps; 300ps; 30ns) with targets in a vacuum chamber are presented. An investigation was made of the optical characteristics of laser plasma in vacuum ultraviolet and X-ray ranges. The intensity of the laser-produced plasma radiation in the range 1–50nm was estimated to be 1010–1012W cm−2. This revised version was published online in November 2006 with corrections to the Cover Date.     

The role of nuclear binding in deep inelastic lepton-nucleon scattering

It is shown that the EMC-effect can be explained by the nuclear structure. The binding of nucleons is shown to play an important role. The contributions of mesons to the nuclear structure functions are discussed.     

Technical fluctuations in a quartz crystal oscillator with automatic gain control

Technical fluctuations in quartz crystal oscillators with automatic gain control (AGC) are studied. Using the example of a three-terminal capacitive transistor circuit, the contribution of technical fluctuations of individual components to the spectral characteristics of the output signal is determined. It is shown that an AGC system can significantly improve the oscillator technical characteristics.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 21, No. 12, pp. 1772–1777, December, 1978.The authors express their gratitude to A. V. Yakimov and A. N. Malakhov for their helpful evluation of the study.     

Effects of a constant electric field in the polariton spectrum of a 1D magnetic photonic crystal with antiferromagnetic interlayer exchange

The effect of a constant external electric field was analyzed and the contribution of the volume fractions of magnetic and nonmagnetic phases to the polariton dynamics of a one-dimensional easy-axial fer-romagnet-nonmagnetic dielectric photonic crystal with a magnetic compensation point was determined using the effective medium method.     

Quasi-ordered nanostructures on the surface of strontium titanate

The results of the investigation of the surface of strontium titanate single crystals after treatment with high-energy plasma are presented. The surface morphology of the strontium titanate single crystals and the change in its characteristics after plasma treatment have been studied using electron scanning and atomicforce microscopy. A change in the electronic state of a part of the titanium ions and a change in the stoichiometry in the modified near-surface layer have been found by the method of valence shift of X-ray lines. A preliminary analysis has been made of the conditions providing the formation of single- and two-level systems of ordered crystallites with sizes of 10⁻⁷–10⁻¹⁰ m on the surface of single-crystal strontium titanate with impurities of ions of the iron and lanthanum groups.