42,882 research outputs found
Effect of inelastic collisions on multiphonon Raman scattering in graphene
We calculate the probabilities of two- and four-phonon Raman scattering in
graphene and show how the relative intensities of the overtone peaks encode
information about relative rates of different inelastic processes electrons are
subject to. If the most important processes are electron-phonon and
electron-electron scattering, the rate of the latter can be deduced from the
Raman spectra
A Finite Size Scaling Study of Lattice Models in the three-dimensional Ising Universality Class
We simulate the spin-1/2 Ising model and the Blume-Capel model at various
values of the parameter D on the simple cubic lattice. We perform a finite size
scaling study of lattices of a linear size up to L=360 to obtain accurate
estimates for critical exponents. We focus on values of D, where the amplitudes
of leading corrections are small. Furthermore we employ improved observables
that have a small amplitude of the leading correction. We obtain
nu=0.63002(10), eta=0.03627(10) and omega=0.832(6). We compare our results with
those obtained from previous Monte Carlo simulations and high temperature
series expansions of lattice models, by using field theoretic methods and
experiments.Comment: 25 pages, 6 figures, typos corrected, references added, conclusions
extende
Case of Almost Redundant Components in 3 alpha Faddeev Equations
The 3 alpha orthogonality condition model using the Pauli-forbidden bound
states of the Buck, Friedlich and Wheatly alpha alpha potential can yield a
compact 3 alpha ground state with a large binding energy, in which a small
admixture of the redundant components can never be eliminated.Comment: Revtex V4.0, 4 pages, no figure
Intersecting D-brane states derived from the KP theory
A general scheme to find tachyon boundary states is developed within the
framework of the theory of KP hierarchy. The method is applied to calculate
correlation function of intersecting D-branes and rederived the results of our
previous works as special examples. A matrix generalization of this scheme
provides a method to study dynamics of coincident multi D-branes.Comment: 10 page
A canonical Frobenius structure
We show that it makes sense to speak of THE Frobenius manifold attached to a
convenient and nondegenerate Laurent polynomialComment: 24 page
Aharanov-Bohm effect for the edge states of zigzag carbon nanotubes
Two delocalized states of metallic zigzag carbon nanotubes near the Dirac
point can be localized by the Aharanov-Bohm magnetic field around 20 Tesla. The
dependence of the localization on the length and diameter of the nanotubes
shows that the localization-delocalization transition can be observed for 2 nm
diameter tube. The mechanism of the localization is explained in terms of the
deformation-induced gauge field, which shows a topological nature of the
localization. The transition from the delocalized states to the localized
states can be observed by scanning tunneling microscopy and spectroscopy. A
similarity between the transition and the spin Hall effect is discussed.Comment: 7 pages, 4 figure
Global analysis of AAC for determining polarized parton distribution functions
We report global analysis results for polarized parton distribution functions
in the nucleon. The optimum distributions are determined by using spin
asymmetry data on polarized lepton scattering on proton, neutron, and deuteron.
Their uncertainties are estimated by the Hessian method. As a result, polarized
quark distributions are relatively well determined, whereas the polarized gluon
distribution has a large uncertainty band. We find that the obtained gluon
distribution is compatible with recent \Delta g/g measurements in high-p_T
hadron productions.Comment: 3 pages, 2 figures, to be published in the proceedings of the XVIIth
Particles and Nuclei International Conference (PANIC), Santa Fe, New Mexico,
USA, October 24-28, 200
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