870 research outputs found
Triangular and Y-shaped hadrons with static sources
The structure of hadrons consisting of three static color sources in
fundamental (baryons) or adjoint (three-gluon glueballs) representations is
studied. The static potentials of glueballs as well as gluon field
distributions in glueballs and baryons are calculated in the framework of field
correlator method.Comment: 7 pages, 5 figures, talk at the NPD-2002 Conference, December 2-6,
ITEP, Moscow, reference adde
Mega-clusters as a tool of interregional cooperation in tourists field
In order to diversify the Russian economy, it is necessary to pay great attention to the emerging sectors of the economy; with a systemic approach they are able to reveal their accumulated potential. Authors consider one of such industries to be the sphere of tourism. Russia has its own unique natural-recreational and cultural-historical potential, which is not fully utilized, and it is confirmed with the relevant statistics. The authors propose to accelerate the development of tourism by raising the level of interregional cooperation from the position of using coexisting competition and competitive coexistence in tourist mega-clusters. Due to the lack of financial resources for separate regions for the tourism development, the implementation of this approach is effective, as it allows achieving savings of money due to economies of scale. The phenomena of coexisting competition and competitive coexistence in the tourism sphere presuppose the unification of the different regions authorities’ efforts for the joint implementation of projects. Regions joining forces on the basis of coexisting competition and competitive coexistence within the mega-clusters will allow each administrative-territorial unit to develop and improve its competitive advantage by asking a stimulus to the development of the other participants. This approach makes it possible to obtain other positive effects noted in the study. Thus, findings broaden the knowledge about the phenomena of coexisting competition and competitive coexistence in the regional economy, about mega-clusters as tools for interregional interactions in the tourism sphere
Phonon switching and combined Fano-Rice effect in optical spectra of bilayer graphene
Recent infrared measurements of phonon peaks in gated bilayer graphene reveal
two striking signatures of electron-phonon interaction: an asymmetric Fano
lineshape and a giant variation of the peak intensity as a function of the
applied gate voltage. In this Letter we provide a unified theoretical framework
which accounts for both these effects and unveils the occurrence of a switching
mechanism between the symmetric () and anti-symmetric () phonon mode
as dominant channel in the optical response. A complete phase diagram of the
optical phonon response is also presented, as a function of both the charge
density and the bandgap.Comment: final versio
CORRELATION-EXTREME NAVIGATION SYSTEM BASED ON MORPHOLOGICAL ANALYSIS
Therefore, advantage of morphological method is associated with the possibility of improving the integration of image registration conditions. Introduced by morphological analysis the notion of «form» significantly enriches the radiometric properties of reference image, making possible to build a more robust detection algorithms
Charged-phonon theory and Fano effect in the optical spectroscopy of bilayer graphene
Since their discovery, graphene-based systems represent an exceptional
playground to explore the emergence of peculiar quantum effects. The present
paper focuses on the anomalous appearence of strong infrared phonon resonances
in the optical spectroscopy of bilayer graphene and on their pronounced
Fano-like asymmetry, both tunable in gated devices. By developing a full
microscopic many-body approach for the optical phonon response we explain how
both effects can be quantitatively accounted for by the quantum interference of
electronic and phononic excitations. We show that the phonon modes borrow a
large dipole intensity from the electronic background, the so-called
charged-phonon effect, and at the same time interfer with it, leading to a
typical Fano response. Our approach allows one to disentangle the correct
selection rules that control the relative importance of the two (symmetric and
antisymmetric) relevant phonon modes for different values of the doping and/or
of the gap in bilayer graphene. Finally, we discuss the extension of the same
theoretical scheme to the Raman spectroscopy, to explain the lack of the same
features on the Raman phononic spectra. Besides its remarkable success in
explaining the existing experimental data in graphene-based systems, the
present theoretical approach offers a general scheme for the microscopic
understanding of Fano-like features in a wide variety of other systems.Comment: 16 pages, 11 eps figures, PR
The QCD vacuum, confinement and strings in the Vacuum Correlator Method
In this review paper the QCD vacuum properties and the structure of color
fields in hadrons are studied using the complete set of gauge-invariant
correlators of gluon fields. Confinement in QCD is produced by the correlators
of some certain Lorentz structure, which violate abelian Bianchi identities and
therefore are absent in the case of QED. These correlators are used to define
an effective colorless field, which satisfies Maxwell equation with nonzero
effective magnetic current. With the help of the effective field and
correlators it is shown that quarks are confined due to effective magnetic
currents, squeezing gluonic fields into a string, in agreement with the ``dual
Meissner effect''. Distribution of effective gluonic fields are plotted in
mesons, baryons and glueballs with static sources.Comment: 36 pages, 19 figures, to appear in UFN, updated version. Few
references added, minor difference
Landau Damping in a 2D Electron Gas with Imposed Quantum Grid
Dielectric properties of semiconductor substrate with imposed two dimensional
(2D) periodic grid of quantum wires or nanotubes (quantum crossbars, QCB) are
studied. It is shown that a capacitive contact between QCB and semiconductor
substrate does not destroy the Luttinger liquid character of the long wave QCB
excitations. However, the dielectric losses of a substrate surface are
drastically modified due to diffraction processes on the QCB superlattice.
QCB-substrate interaction results in additional Landau damping regions of the
substrate plasmons. Their existence, form and the density of losses are
strongly sensitive to the QCB lattice constant.Comment: 9 pages, 12 eps-figure
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