Vol 52, No 2 (2017)

The dynamics of correlation of photon number fluctuations of interacting modes for the process of intracavity third subharmonic generation is investigated. It is shown that the entangled field states by the variables of photon number can be obtained in this system. The quantum dynamics of the photons number, the quantum entropy and the Wigner function of the stationary states of the fundamental mode and the third subharmonic mode have also been studied. It is found that the dynamics of these quantities depends highly on the value of the coupling coefficient of the interacting modes. It is shown that at long interaction times and for the large values of the coupling coefficient of the modes, the mode of the third subharmonic is localized in the three-component state with the same probability of detection of the mode in each component of the state. The quantum entropy of the state is less than the maximal entropy of the three-component state ln3, which points out the presence of quantum mechanical interference between the components of the state of third subharmonic mode.

As an instrument for Korea Multi-purpose Accelerator Complex (KOMAC) facility proton beam profiling, a vibrating wire monitor (VWM) has been installed and tested at TR23 target room. Experiments were done at very low (100 nA) beam current conditions. At the number of particles about 10¹¹ proton/train and trains repetition rate of 0.1 Hz we have measured the beam profile by a few scanning steps. The experience accumulated in these experiments turned out to be useful for the VWM upgrades (e. g. understanding interactions of protons with wire materials and heat transfer processes) and will be particularly helpful for the KOMAC beam halo measurements in the future high-current operation.

The electronic states in a conical quantum dot in the framework of the adiabatic approximation as well as the combined approach with the perturbation theory have been considered. The obtained results have been compared with the results of numerical methods–the finite element and the Arnoldi methods. The interpolation formula for the energy correction and its dependence on the geometric parameters of the conical quantum dot have been obtained. The comparing of the wave functions obtained by different methods and the range of applicability of different methods have been defined. The dependence of the z-component of the dipole moment on the geometric parameters of the structure has been considered.

One-domain Ni@C nanoparticles encapsulated in carbon coating have been investigated depending on the size and concentration of Ni in carbon. The nanoparticles of nickel were prepared with the average diameters changing in a broad range of 4–45 nm, and the concentration of Ni in C varies in 2–12 wt%. To prepare the Ni@C nanocomposites the solid solutions of nickel phthalocyanine–metal-free phthalocyanine (NiPc)_x(H₂Pc)_1–x, 0 ≤ x ≤ 1 were synthesized and the solidphase pyrolysis of these compounds was performed. In the case of ultradispersive Ni nanoparticles (the interval of quantum dots is 1–10 nm), a considerable shift of the resonance field and broadening of resonance absorption field were revealed in the spectra of FMR at room temperature. The data were interpreted taking into account the essential contribution of the surface magnetic anisotropy, the magnetic field of which far exceeds the magnetic field of volume anisotropy.

An expression for local period of interferometric moire fringes is obtained in the eikonal approximation. The earlier developed theory was employed for the case of temperature gradient in the mirror block of the interferometer. The geometric shape, the intensity distribution, and the dependence of local period of moire fringes on the coordinates were obtained. It was shown that in the direction of applied gradient the fringes are of purely dilatational type, while in the perpendicular direction they are of purely rotational type.

The melting of the DNA–ligand complex is considered theoretically for the ligands binding with the DNA by two mechanisms. The obtained results describe the experimentally observed behavior of such quantities as the denaturation degree and the correlation length depending on the concentration of ligands. It is shown that the heat and cold denaturations of the DNA–ligand complexes exhibit the same cooperativity, as the heat denaturation of the pure DNA. At the same time, the temperature range of the cold denaturation is essentially narrower than the interval for the heat denaturation of the pure DNA and the DNA–ligand complexes.