10,972 research outputs found
Search for and strangeonium-like structures
Theoretically, it has been presumed from an effective Lagrangian calculation
that there could exist two charged strangeonium-like molecular states
and , with and
configurations respectively. In the framework of QCD sum rules, we predict that
masses of () and ()
are and respectively, which are both above
their respective two meson thresholds. We suggest to put in practice the search
for these two charged strangeonium-like structures in future experiments.Comment: 7 pages, 4 eps figures; the version accepted for publication in PRD.
arXiv admin note: text overlap with arXiv:1203.070
Non-Fermi Liquid Behavior In Quantum Critical Systems
The problem of an electron gas interacting via exchanging transverse gauge
bosons is studied using the renormalization group method. The long wavelength
behavior of the gauge field is shown to be in the Gaussian universality class
with a dynamical exponent in dimensions .
This implies that the gauge coupling constant is exactly marginal. Scattering
of the electrons by the gauge mode leads to non-Fermi liquid behavior in . The asymptotic electron and gauge Green's functions, interaction
vertex, specific heat and resistivity are presented.Comment: 9 pages in REVTEX 2.0. Submitted to Phys. Rev. Lett. 3 figures in
postscript files can be obtained at [email protected]. The filename is
gan.figures.tar.z and it's compressed. You can uncompress it by using
commands: "uncompress gan.figures.tar.z" and "tar xvf gan.figures.tar
Theory for Gossamer and Resonating Valence Bond Superconductivity
We use an effective Hamiltonian for two-dimensional Hubbard model including
an antiferromagnetic spin-spin coupling term to study recently proposed
gossamer superconductivity. We formulate a renormalized mean field theory to
approximately take into account the strong correlation effect in the partially
projected Gutzwiller wavefucntions. At the half filled, there is a first order
phase transition to separate a Mott insulator at large Coulomb repulsion U from
a gossamer superconductor at small U. Away from the half filled,the Mott
insulator is evolved into an resonating valence bond state, which is
adiabatically connected to the gossamer superconductor.Comment: 10 pages, 13 figure
Effects of image charges, interfacial charge discreteness, and surface roughness on the zeta potential of spherical electric double layers
We investigate the effects of image charges, interfacial charge discreteness,
and surface roughness on spherical electric double layers in electrolyte
solutions with divalent counter-ions in the setting of the primitive model. By
using Monte Carlo simulations and the image charge method, the zeta potential
profile and the integrated charge distribution function are computed for
varying surface charge strengths and salt concentrations. Systematic
comparisons were carried out between three distinct models for interfacial
charges: 1) SURF1 with uniform surface charges, 2) SURF2 with discrete point
charges on the interface, and 3) SURF3 with discrete interfacial charges and
finite excluded volume. By comparing the integrated charge distribution
function (ICDF) and potential profile, we argue that the potential at the
distance of one ion diameter from the macroion surface is a suitable location
to define the zeta potential. In SURF2 model, we find that image charge effects
strongly enhance charge inversion for monovalent interfacial charges, and
strongly suppress charge inversion for multivalent interfacial charges. For
SURF3, the image charge effect becomes much smaller. Finally, with image
charges in action, we find that excluded volumes (in SURF3) suppress charge
inversion for monovalent interfacial charges and enhance charge inversion for
multivalent interfacial charges. Overall, our results demonstrate that all
these aspects, i.e., image charges, interfacial charge discreteness, their
excluding volumes have significant impacts on the zeta potential, and thus the
structure of electric double layers.Comment: 11 pages, 10 figures, some errors are change
Effects of fault transmissivity on the potential of fault reactivation and induced seismicity : Implications for understanding induced seismicity at Pohang EGS
Funding Information: The project leading to part of the results in this article received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 691728 .Peer reviewedPublisher PD
On the low energy properies of fermions with singular interactions
We calculate the fermion Green function and particle-hole susceptibilities
for a degenerate two-dimensional fermion system with a singular gauge
interaction. We show that this is a strong coupling problem, with no small
parameter other than the fermion spin degeneracy, N. We consider two
interactions, one arising in the context of the model and the other in
the theory of half-filled Landau level. For the fermion self energy we show in
contrast to previous claims that the qualitative behavior found in the leading
order of perturbation theory is preserved to all orders in the interaction. The
susceptibility at a general wavevector retains
the fermi-liquid form. However the susceptibility either
diverges as or remains finite but with nonanalytic wavevector,
frequency and temperature dependence. We express our results in the language of
recently discussed scaling theories, give the fixed-point action, and show that
at this fixed point the fermion-gauge-field interaction is marginal in ,
but irrelevant at low energies in .Comment: 21 pages, uuencoded LATEX file with included Postscript figures, R
Impurity correlations in dilute Kondo alloys
The single impurity Kondo model is often used to describe metals with dilute
concentrations (n_i) of magnetic impurities. Here we examine how dilute the
impurities must be for this to be valid by developing a virial expansion in
impurity density. The O(n_i^2) term is determined from results on the
2-impurity Kondo problem by averaging over the RKKY coupling. The non-trivial
fixed point of the 2-impurity problem could produce novel singularities in the
heat capacity of dilute alloys at O(n_i^2).Comment: 6 pages, no figure
Multi-Channel Kondo Necklace
A multi--channel generalization of Doniach's Kondo necklace model is
formulated, and its phase diagram studied in the mean--field approximation. Our
intention is to introduce the possible simplest model which displays some of
the features expected from the overscreened Kondo lattice. The conduction
electron channels are represented by sets of pseudospins \vt_{j}, , which are all antiferromagnetically coupled to a periodic array of
|\vs|=1/2 spins. Exploiting permutation symmetry in the channel index
allows us to write down the self--consistency equation for general . For
, we find that the critical temperature is rising with increasing Kondo
interaction; we interpret this effect by pointing out that the Kondo coupling
creates the composite pseudospin objects which undergo an ordering transition.
The relevance of our findings to the underlying fermionic multi--channel
problem is discussed.Comment: 29 pages (2 figures upon request from [email protected]), LATEX,
submitted for publicatio
Instability of the Fermi-liquid fixed point in an extended Kondo model
We study an extended SU(N) single-impurity Kondo model in which the impurity
spin is described by a combination of Abrikosov fermions and Schwinger bosons.
Our aim is to describe both the quasiparticle-like excitations and the locally
critical modes observed in various physical situations, including non-Fermi
liquid (NFL) behavior in heavy fermions in the vicinity of a quantum critical
point and anomalous transport properties in quantum wires. In contrast with
models with either pure bosonic or pure fermionic impurities, the strong
coupling fixed point is unstable against the conduction electron kinetic term
under certain conditions. The stability region of the strong coupling fixed
point coincides with the region where the partially screened, effective
impurity repels the electrons on adjacent sites. In the instability region, the
impurity tends to attract electrons to the neighboring sites, giving
rise to a double-stage Kondo effect with additional screening of the impurity.Comment: 10 pages, 2 figures, Proceedings of the NATO Workshop on "Concepts in
Electron Correlations", Hvar,October 200
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