1,771 research outputs found
Dark resonances in the field of frequency shifted feedback laser radiation
We present a theory of dark resonances in a fluorescence of a three-level
atom gas interacting with a polychromatic field of a frequency shifted feedback
(FSF) laser. We show that conditions for the resonance observation are optimal
when the phase relations between the laser spectral components provide
generation of a light pulses train. We study analytically the field broadening
and the light shift of the resonances.Comment: 18 pages, 8 figure
Electron-electron interaction in carbon nanostructures
The electron-electron interaction in carbon nanostructures was studied. A new
method which allows to determine the electron-electron interaction constant
from the analysis of quantum correction to the magnetic
susceptibility and the magnetoresistance was developed. Three types of carbon
materials: arc-produced multiwalled carbon nanotubes (arc-MWNTs), CVD-produced
catalytic multiwalled carbon nanotubes (c-MWNTs) and pyrolytic carbon were used
for investigation. We found that =0.2 for arc-MWNTs (before and
after bromination treatment); = 0.1 for pyrolytic graphite;
0 for c-MWNTs. We conclude that the curvature of graphene layers
in carbon nanostructures leads to the increase of the electron-electron
interaction constant .Comment: 12 pages, 18 figures, to be published in the Proceedings of the NATO
Advanced Research Workshop on Electron Correlation in New Materials and
Nanosystems, NATO Science Series II, Springer, 200
The High Eccentricity of the Planet Around 16 Cyg B
We consider the high eccentricity, 0.66, of the newly discovered planet
around 16 Cyg B, using the fact that the parent star is part of a wide binary.
We show that the high eccentricity of the planet could be the result of tidal
forces exerted on 16 Cyg B and its planet by 16 Cyg A, the distant companion in
the system. By following stellar triple systems with parameters similar to
those of 16 Cyg, we have established that the orbital eccentricity of the
planet could have gone through strong modulation, with an amplitude of 0.8 or
even larger, with typical timescale of tens of millions years. The amplitude of
the planet eccentricity strongly depends on the relative inclination between
the plane of motion of the planet and that of the wide binary 16 Cyg AB. To
account for the present eccentricity of the planet we have to assume that the
angle between the two planes of motion is large, at least 60 deg. We argue that
this assumption is reasonable for wide binaries like 16 Cyg AB.Comment: 2 Figures, Latex, submitted for publication to ApJ
Innovations and support for quality in agriculture : a case study
The aim of the article is to investigate the economic and legal aspects of integrating innovations in agriculture and supporting the quality of agricultural products in the context of modern Russia.
Throughout the process of research, the authors analyzed the directions of agricultural sector development, mechanisms of quality and safety support, as well as customer rights protection.
As a result the authors have agreed on, the need to integrate cluster models in the agricultural sector, notably in the bee-keeping, seed production (including financing of this activity), as well as legislative stimulus to shift towards «green» biotechnology in the domestic agriculture.
Based on the research conducted, the authors have proposed mechanisms to improve the current Russian legislation in the spheres of innovation development and support for quality and safety of agricultural production.peer-reviewe
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