158,914 research outputs found
Finite-Size Effects in the Field Theory Above the Upper Critical Dimension
We demonstrate that the standard O(n) symmetric field theory does
not correctly describe the leading finite-size effects near the critical point
of spin systems on a -dimensional lattice with . We show that these
finite-size effects require a description in terms of a lattice Hamiltonian.
For and explicit results are given for the susceptibility
and for the Binder cumulant. They imply that recent analyses of Monte-Carlo
results for the five-dimensional Ising model are not conclusive.Comment: 4 pages, latex, 1 figur
On a class of reductions of Manakov-Santini hierarchy connected with the interpolating system
Using Lax-Sato formulation of Manakov-Santini hierarchy, we introduce a class
of reductions, such that zero order reduction of this class corresponds to dKP
hierarchy, and the first order reduction gives the hierarchy associated with
the interpolating system introduced by Dunajski. We present Lax-Sato form of
reduced hierarchy for the interpolating system and also for the reduction of
arbitrary order. Similar to dKP hierarchy, Lax-Sato equations for (Lax
fuction) due to the reduction split from Lax-Sato equations for (Orlov
function), and the reduced hierarchy for arbitrary order of reduction is
defined by Lax-Sato equations for only. Characterization of the class of
reductions in terms of the dressing data is given. We also consider a waterbag
reduction of the interpolating system hierarchy, which defines
(1+1)-dimensional systems of hydrodynamic type.Comment: 15 pages, revised and extended, characterization of the class of
reductions in terms of the dressing data is give
Phase transition in site-diluted Josephson junction arrays: A numerical study
We numerically investigate the intriguing effects produced by random
percolative disorder in two-dimensional Josephson-junction arrays. By dynamic
scaling analysis, we evaluate critical temperatures and critical exponents with
high accuracy. It is observed that, with the introduction of site-diluted
disorder, the Kosterlitz-Thouless phase transition is eliminated and evolves
into a continuous transition with power-law divergent correlation length.
Moreover, genuine depinning transition and creep motion are studied, evidence
for distinct creep motion types is provided. Our results not only are in good
agreement with the recent experimental findings, but also shed some light on
the relevant phase transitions.Comment: 7 pages, 8 figures, Phys. Rev. B (in press
Quantum criticality in a Mott pn-junction in an armchair carbon nanotube
In an armchair carbon nanotube pn junction the p- and n- regions are
separated by a region of a Mott insulator, which can backscatter electrons only
in pairs. We predict a quantum-critical behavior in such a pn junction.
Depending on the junction's built-in electric field E, its conductance G scales
either to zero or to the ideal value G=4e^2/h as the temperature T is lowered.
The two types of the G(T) dependence indicate the existence, at some special
value of E, of an intermediate quantum critical point with a finite conductance
G<4e^2/h. This makes the pn junction drastically different from a simple
barrier in a Luttinger liquid.Comment: 5 pages, 1 figur
On surface plasmon polariton wavepacket dynamics in metal-dielectric heterostructures
The WKB equations for dynamics of the surface plasmon polariton (SPP)
wavepacket are studied. The dispersion law for the SPP in the metal-dielectric
heterostructure with varying thickness of a perforated dielectric layer is
rigorously calculated and investigated using the scattering matrix method. Two
channels of the SPP wavepacket optical losses related to the absorption in a
metal and to the SPP leakage are analyzed. It is shown that change of the
dielectric layer thickness acts on the SPP as an external force leading to
evolution of its quasimomentum and to the wavepacket reversal or even to the
optical Bloch oscillations (BO). Properties of these phenomena are investigated
and discussed. Typical values of the BO amplitude are about tens of microns and
the period is around tens or hundreds of femtoseconds.Comment: 12 pages, 5 figure
Y(4260) --> gamma + X(3872) in the diquarkonium picture
The observed Y(4260)\to \gamma + X(3872) decay is a natural consequence of
the diquark-antidiquark description of Y and X resonances. In this note we
attempt an estimate of the transition rate, \Gamma_{\rm rad}, by a
non-relativistic calculation of the electric dipole term of a diquarkonium
bound state. We compute \Gamma_{\rm rad} for generic composition values of the
isospin of X and Y. Specializing to I=0 for X(3872), we find \Gamma_{\rm rad}=
496~keV for Y(4260) with I=0 and \Gamma_{\rm rad}= 179~keV for I=1. Combining
with BESIII data, we derive upper bounds to B(Y\to J/\Psi+\pi+\pi) and to
\Gamma(Y\to \mu^+ \mu^-). We expect to confront these results with forthcoming
data from electron-positron and hadron colliders.Comment: references added and minor corrections, 11 pages, 1 figur
Demonstration of optically modulated dispersion forces
We report the first experiment on the optical modulation of dispersion forces
through a change of the carrier density in a Si membrane. For this purpose a
high-vacuum based atomic force microscope and excitation light pulses from an
Ar laser are used. The experimental results are compared with two theoretical
models. The modulation of the dispersion force will find applications in
optomechanical micromachines.Comment: 7 pages, 3 figures, opex3.sty is used, text has been made in
accordance with the final version to appear in Optics express, 3 misprints
are correcte
Recommended from our members
Advances in test and measurement of the interface adhesion and bond strengths in coating-substrate systems, emphasising blister and bulk techniques
In this paper, recent advances in the minimum-destructive testing of the adhesion of coating-substrate systems are reviewed, focusing on key techniques such as micro- and nano-scale levels of indentation, scratching, laser-induced wave shock, as well as the blister and buckle approach. Along with adhesion failure tests, the latest and most extensive applications of the adhesion test methods in nano-, micro- and bulk-coating technology and the associated techniques to determine the minimum damage defects left on the coatings are discussed and their use reviewed
- …