卷 104, 编号 3 (2016)

The energy levels of the fermions bound to the vortex are considered for vortices in the superfluid/superconducting systems that contain the symmetry protected plane of zeroes in the gap function in bulk. The Caroli–de Gennes–Matricon branches with different approach zero energy level at p_z → 0. The density of states of the bound fermions diverges at zero energy giving rise to the \(\sqrt \Omega \) dependence of the density of states in the polar phase of superfluid ³He rotating with the angular velocity Ω and to the \(\sqrt B \) dependence of the density of states for superconductors in the (d_xz + id_yz)-wave pairing state.

The thermally activated fracture processes in the carbon backbone of diamond-like carbon nanothreads and the hydrogen desorption from them has been studied by the molecular dynamics method. Specifically, the temperature dependence of the characteristic desorption time at T = 1700−2800 K has been determined. The activation energy and frequency factor in the Arrhenius formula for the desorption rate are found. This allows estimating the desorption time at any temperature. The mechanical stiffness of nanothreads is calculated.

The e⁺e⁻ → γ* → π⁰γ process was considered using time-like pion transition form factor, obtained in the approach of the Anomaly Sum Rules (ASR). The total cross section and angular distribution of the process was calculated. As the result of the comparison with the data, it was shown that ASR approach provides their good description in the regions far from the pole. Also there was proposed a method allowing a reasonable description of data in the region of pole within the ASR approach. The strong restrictions for the parameters of the modified ASR approach were obtained.

A luminescent trace has been observed in a ruby crystal (Al₂O₃: Cr³⁺) that rotates at a frequency of 2 to 200 Hz and is irradiated by 532-nm coherent electromagnetic radiation. A method has been proposed to determine the lifetime of the excited electronic state of chromium ions from the measurement of the length of an arc of the trajectory of a light spot on the surface of a rotating ruby single crystal. A “comet trace” formed at the passage of radiation through the rotating crystal near the absorption band of the material has been detected inside the ruby crystal. It has been shown that the theory based on the analysis of the motion of polaritons in the rotating reference frame is in satisfactory agreement with experimental results.

The fine structure of the emission spectrum of a quasi-two-dimensional electron–hole liquid in shallow SiGe/Si quantum wells is observed experimentally. This fine structure is explained by the occurrence of steps in the density of states resulting from the coexistence of light and heavy holes in the liquid phase and by the interaction of charge carriers with charge-density oscillations in the liquid.

A law determining the dispersion shift of the anti-Stokes band of the supercontinuum of a light bullet in a filament of a femtosecond laser pulse in transparent dielectrics has been established. The dispersion equation theoretically obtained for the anti-Stokes shift has been confirmed by spectroscopic studies of the filamentation of the near and middle infrared ranges in fused silica and fluorides.

The voltage–current characteristics of a discharge at atmospheric pressure in a wide range of discharge currents have been numerically studied within a hybrid model for a gas-discharge plasma with a self-consistent description of the heating of a cathode. Segments corresponding to a normal glow discharge, a transition from a glow discharge to an arc discharge, and an arc discharge have been revealed on the voltage–current characteristics. All main parameters of the plasma have been obtained for each of these segments of the voltage–current characteristics of the discharge.

The theory of the interaction of a two-dimensional gas of indirect dipolar excitons with Rayleigh surface elastic waves has been developed. The absorption and renormalization of the phase velocity of a surface wave, as well as the drag of excitons by the surface acoustic wave and the generation of bulk acoustic waves by a twodimensional gas of dipolar excitons irradiated by external electromagnetic radiation, have been considered. These effects have been studied both in a normal phase at high temperatures and in a condensed phase of the exciton gas. The calculations have been performed in the ballistic and diffusion limits for both phases.