Electron–Phonon Scattering and Conductivity of a Quantum Cylinder in a Magnetic Field
The contribution of electron–phonon scattering to conductivity of a quantum cylinder in a lon-gitudinal magnetic field has been studied. It has been shown that the conductivity of the nanotube undergoes Aharonov–Bohm oscillations with variations in the magnetic flux through the nanotube cross section. The formulas describing the temperature dependence of the resistance of the nanostructure both in the case of an isotropic phonon spectrum and with allowance for the effects of phonon confinement have been obtained in the analytical form.
A contribution of the electron-phonon scattering to the conductivity of a quantum cylinder in a magnetic field is calculated. It is demonstrated that the nanotube conductivity undergoes the Aharonov–Bohm oscillations with changes of the magnetic flux through the nanotube cross section.
In operation results of computer simulation of characteristics of the standard analog device - the heterodyne executed on the printed circuit board from the composite dielectric having feeble conductivity are explained. Results of simulation showed that increase in specific bulk conductivity of material of the printed circuit board to 2·10 -7 Ohm -1 -m -1 practically does not change operating characteristics of a heterodyne. The possibility of effective use of the composite poorly carrying out dielectrics in standard radio engineering devices allowing to prevent origin of electrostatic discharges is set.
The photoemission of excess charge carriers into high-ohmic gallium arsenide was investigated. It was revealed, that the illumination even small local sample areas located far from contacts, influences both on contacts transition resistance and on volume conductivity of the crystal. On Suite-voltage dependencies there is a linear plot, angular coefficient which is directly proportional to the diameter of the illuminated surface. The model qualitatively explain the experimental results.
In quiet low-latitude Earth's ionosphere, a rather developed current system that is responsible for the Sq magnetic-field variations is formed in quiet sunny days under the action of tidal streams. The density of the corresponding currents is maximal at the equatorial latitudes in the midday hours, where the so-called equatorial current jet is formed. In this work, we discuss the nature of the equatorial current jet. The original part of this paper is dedicated to the study of the value of its response to external effects. First of all, it is related to estimating the possibility of using the equatorial current jet for generating the low-frequency electromagnetic signals during periodic heating of the ionosphere by the heating-facility radiation. The equatorial current jet can also produce electrodynamic response to the natural atmospheric processes, e.g., an acoustic-gravitational wave.
Investigated the effect of annealing on the optical properties of metallic films obtained by setting the plasma-focus "PF-4" on glass substrates. The transmission spectra of these films before and after annealing in air at about 900 K for about 10 minutes. Shows the effect of carbon on the optical properties and electrical conductivity of the films.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.