103,231 research outputs found
Matrix Model Calculations beyond the Spherical Limit
We propose an improved iterative scheme for calculating higher genus
contributions to the multi-loop (or multi-point) correlators and the partition
function of the hermitian one matrix model. We present explicit results up to
genus two. We develop a version which gives directly the result in the double
scaling limit and present explicit results up to genus four. Using the latter
version we prove that the hermitian and the complex matrix model are equivalent
in the double scaling limit and that in this limit they are both equivalent to
the Kontsevich model. We discuss how our results away from the double scaling
limit are related to the structure of moduli space.Comment: 44 page
Realistic interatomic potential for MD simulations
The coefficients of interatomic potential of simple form Exp-6 for neon are
obtained. Repulsive part is calculated ab-initio in the Hartree-Fock
approximation using the basis of atomic orbitals orthogonalized exactly on
different lattice sites. Attractive part is determined empirically using single
fitting parameter. The potential obtained describes well the equation of state
and elastic moduli of neon crystal in wide range of interatomic distances and
it is appropriate for molecular dynamic simulations of high temperature
properties and phenomena in crystals and liquids.Comment: MikTex v.2.1 (AMS-TEX),11 pages, 3 EPS figure
Edge and waveguide THz surface plasmon modes in graphene micro-ribbons
Surface plasmon modes supported by graphene ribbon waveguides are studied and
classified. The properties of both modes with the field concentration within
the ribbon area (waveguiding modes) and on the edges (edge modes) are
discussed. The waveguide and edge modes are shown to be separated from each
other by a gap in wavenumbers. The even-parity hybridized edge mode results to
be the fundamental electromagnetic mode of the ribbon, possessing also the
lowest losses. All the plasmonic modes in the ribbons have an optimum
frequency, at which the absorption losses are minimum, due to competition
between the plasmon confinement and the frequency dependence of absorption in
graphene.Comment: 4 pages, 4 figure
Separable Structure of Many-Body Ground-State Wave Function
We have investigated a general structure of the ground-state wave function
for the Schr\"odinger equation for identical interacting particles (bosons
or fermions) confined in a harmonic anisotropic trap in the limit of large .
It is shown that the ground-state wave function can be written in a separable
form. As an example of its applications, this form is used to obtain the
ground-state wave function describing collective dynamics for trapped
bosons interacting via contact forces.Comment: J. Phys. B: At. Mol. Opt. Phys. 33 (2000) (accepted for publication
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