Modern Physics Letters B

This paper reviews the method of bosonization for one-dimensional interacting fermions. Example of its application to mesoscopic systems is presented with an explicit calculation of the spin and charge currents in an interacting quantum wire subject to a uniform magnetic field and alternating voltage source. Special emphasis is given to the details of the calculation using bosonization and Keldysh techniques.

Single crystals of copper succinate dihydrate (CSD) with triclinic structure were grown in silica gel medium. The functional groups in the crystal were analyzed by FT-IR Spectroscopy. Atomic Force Microscopy (AFM) revealed the striations on the surface of grown crystals, which were incorporated during its time of growth. Thermal degradation studies have been carried out by Differential Scanning Calorimetry (DSC). Dielectric constant and AC conductivity have been estimated as a function of frequency at different temperatures.

Mechanism of resistance switching in heterostructure Au/LaMnO₃/SrNb_0.01Ti_0.99O₃ was investigated. In Au/LaMnO₃/SrNb_0.01Ti_0.99O₃ devices the LaMnO₃ films were fabricated under various oxygen pressures. The content of the oxygen vacancies has a significant impact on the resistance switching performance. We propose that the resistance switching characteristics of Au/LaMnO₃/SrNb_0.01Ti_0.99O₃ arise from the modulation of the Au/LaMnO₃ Schottky barrier due to the change of the oxygen vacancy concentration at Au/LaMnO₃ interface under the external electric field. The effect of the oxygen vacancy concentration on the resistance switching is explained based on the self-consistent calculation. Both the experimental and numerical results confirm the important role of the oxygen vacancies in the resistance switching behavior.

In this paper, we report on the influence of an internal defect on the vortex entrance in a mesoscopic superconducting sample. Effects associated to the pinning force of the defect on the configuration and on the vortex entry fields are studied for a very thin disk. We calculate the supercurrent, magnetization, vorticity, free energy and Cooper pairs density for a disk in presence of external magnetic field applied perpendicular to the disk plane. Due to vortex–defect attraction (repulsion), the vortices always (never) are found to be sitting on the defect position.

This is an analytical investigation of well-known 10–12 potential of hydrogen–hydrogen covalent bond. In this research, we will make an elaboration of the well-known 6–12 Lennard–Jones potential in case of this type of bond. Though the results are illustrated in many text books and literature, an analytical analysis for these potentials is missing almost everywhere. The power laws are valid for small radial distances, which are calculated to some extent. The internuclear separation as well as the binding energy of the hydrogen molecule are evaluated with success.

A BiFeO₃ thin film was prepared on the (111) Pt/Ti/SiO₂/Si substrate by the solution coating method. In order to detect the effect of an external magnetic field on the BiFeO₃ thin film, a fine scan X-ray diffraction with a scan ratio of 0.002°/s was carried out under the magnetic field parallel to the film surface. The result of the in situ analysis of X-ray diffraction for the thin film in the magnetic field indicates that the magnetic field leads to an increase of the integral intensity ratio of compared with that under no magnetic field. The increase of implies a domain switching under the magnetic field, where the domain switching comes from the decreasing residual tensile stress induced by the magnetostriction of BiFeO₃ in the magnetic field.

In this paper, we investigate the nonequilibrium geometric phase (GP) of a spin chain system whose two end spins are respectively coupled to thermal reservoirs at different temperatures. In the spin chain, there exists the XX-type spin interaction and an external field is applied to each spin. An analytical expression for the GP is found in the weak coupling limit. The influences of various parameters on the deviation of GP from the unitary one are investigated. It is found that the GP is more stable against the decoherence when the external field is homogenously applied. In addition, the present result may provide a useful approach to the maintenance of GP in the nonequilibrium system.

In this work, Ag nanoparticles were deposited on quartz glass substrates by magnetron sputtering method, and the morphology was characterized by SEM. Ag nanoparticle surface plasmon resonance characteristics were observed by transmittance measurement. The experimental results demonstrated an increase in particle size that was correlated to an increase in sputtering time and a plasmon resonance absorption peak redshift. This phenomenon was partially explained by Mie scattering model. The differences between our theoretical analysis and experimental results show that both the shape of and the spacing between nanoparticles are key parameters affecting plasmon resonance peak location.

This paper reports the fabrication of Ag/N-BuHHPDI/p-Si heterojunction diode by evaporating a layer of organic compound N-Butyl-N'-(6-hydroxyhexyl) perylene-3,4,9,10-tetracarboxylicacid-diimide (N-BuHHPDI) on top of the p-Si. The electronic properties of the heterojunction have been studied, in dark at a temperature of 300 K, by conventional current–voltage (I–V) method, Norde's method and Cheung's technique. By analyzing conventional I–V characteristics, the device exhibited rectifying behavior with a rectification ratio of 62.67 at ± 5.8 V. From the forward biased I–V measurements, the barrier height and ideality factor values of 0.83 eV and 6.4, respectively, have been obtained. Different diode parameters such as series resistance, shunt resistance, reverse saturation current and turn on voltage have been extracted from the I–V measurements. The parameters calculated from Norde's and Cheung's methods are found to be in good agreement with those calculated from conventional I–V measurements. Morphology of the N-BuHHPDI film is investigated using atomic force microscope (AFM).