1,073 research outputs found
Single File Diffusion of particles with long ranged interactions: damping and finite size effects
We study the Single File Diffusion (SFD) of a cyclic chain of particles that
cannot cross each other, in a thermal bath, with long ranged interactions, and
arbitrary damping. We present simulations that exhibit new behaviors
specifically associated to systems of small number of particles and to small
damping. In order to understand those results, we present an original analysis
based on the decomposition of the particles motion in the normal modes of the
chain. Our model explains all dynamic regimes observed in our simulations, and
provides convincing estimates of the crossover times between those regimes.Comment: 30 pages, 9 figure
Single File Diffusion enhancement in a fluctuating modulated 1D channel
We show that the diffusion of a single file of particles moving in a
fluctuating modulated 1D channel is enhanced with respect to the one in a bald
pipe. This effect, induced by the fluctuations of the modulation, is favored by
the incommensurability between the channel potential modulation and the moving
file periodicity. This phenomenon could be of importance in order to optimize
the critical current in superconductors, in particular in the case where mobile
vortices move in 1D channels designed by adapted patterns of pinning sites.Comment: 4 pages, 4 figure
Le champ lexical « étendues d’eau » et quelques vocables apparentés dans le Dictionnaire explicatif et combinatoire du français contemporain (12 vocables)
Cet article, qui s’inscrit dans l’optique du Dictionnaire explicatif et combinatoire du français contemporain, traite d’un champ lexical comportant des noms concrets et présentant un système de définitions structuré de façon rigide et précise. On énoncera trois principes lexicographiques, qui nous permettront de distinguer clairement les diverses composantes sémantiques qui constitueront ces définitions. Les composantes exprimant la dimension occupent une place importante dans notre article, vu leur caractère relatif. On expliquera les notions de ‘moyenne’ et ‘extrême’ ainsi que d’‘échelle dimensionnelle’.This article, written within the framework of the Explanatory Combinatorial Dictionary of Modern French, deals with a lexical field composed of concrete nouns, which presents a system of definitions structured in a rigid and precise way. The three lexicographic principles to be stated, will allow us to clearly distinguish the different semantic components that will constitute these definitions. The components conveying the dimensional meaning occupy a special place because of their relative character. The concepts of 'average size' and 'extreme size' are introduced together with 'dimensional scale'
Configurational entropy of Wigner crystals
We present a theoretical study of classical Wigner crystals in two- and
three-dimensional isotropic parabolic traps aiming at understanding and
quantifying the configurational uncertainty due to the presence of multiple
stable configurations. Strongly interacting systems of classical charged
particles confined in traps are known to form regular structures. The number of
distinct arrangements grows very rapidly with the number of particles, many of
these arrangements have quite low occurrence probabilities and often the
lowest-energy structure is not the most probable one. We perform numerical
simulations on systems containing up to 100 particles interacting through
Coulomb and Yukawa forces, and show that the total number of metastable
configurations is not a well defined and representative quantity. Instead, we
propose to rely on the configurational entropy as a robust and objective
measure of uncertainty. The configurational entropy can be understood as the
logarithm of the effective number of states; it is insensitive to the presence
of overlooked low-probability states and can be reliably determined even within
a limited time of a simulation or an experiment.Comment: 12 pages, 8 figures. This is an author-created, un-copyedited version
of an article accepted for publication in J. Phys.: Condens. Matter. IOP
Publishing Ltd is not responsible for any errors or omissions in this version
of the manuscript or any version derived from it. The definitive
publisher-authenticated version is available online at
10.1088/0953-8984/23/7/075302.
On the theory of the vortex state in the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase
We demonstrate that the vortex state in the Fulde-Ferrell-Larkin-Ovchinnikov
(FFLO) phase may be very different depending on the field orientation relative
to the crystalline axes. We calculate numerically the upper critical field near
the tricritical point taking into account the modulation of the order parameter
along the magnetic field as well as the higher Landau levels. For s-wave
superconductors with the anisotropy described by an elliptical Fermi surface we
propose a general scheme of the analysis of the angular dependence of upper
critical field at all temperatures on the basis of the exact solution for the
order parameter. Our results show that the transitions (with tilting magnetic
field) between different types of mixed states may be a salient feature of the
FFLO phase. Moreover we discuss the reasons for the first-order phase
transition into the FFLO state in the case of CeCoIn5 compound.Comment: 7 figure
Nonequilibrium thermodynamics versus model grain growth: derivation and some physical implications
Nonequilibrium thermodynamics formalism is proposed to derive the flux of
grainy (bubbles-containing) matter, emerging in a nucleation growth process.
Some power and non-power limits, due to the applied potential as well as owing
to basic correlations in such systems, have been discussed. Some encouragement
for such a discussion comes from the fact that the nucleation and growth
processes studied, and their kinetics, are frequently reported in literature as
self-similar (characteristic of algebraic correlations and laws) both in basic
entity (grain; bubble) size as well as time scales.Comment: 8 pages, 1 figur
Is there a way to measure implementation of integration in different countries? The case of the PRISMA implementation qualitative methodology
Deformed strings in the Heisenberg model
We investigate solutions to the Bethe equations for the isotropic S = 1/2
Heisenberg chain involving complex, string-like rapidity configurations of
arbitrary length. Going beyond the traditional string hypothesis of undeformed
strings, we describe a general procedure to construct eigenstates including
strings with generic deformations, discuss general features of these solutions,
and provide a number of explicit examples including complete solutions for all
wavefunctions of short chains. We finally investigate some singular cases and
show from simple symmetry arguments that their contribution to zero-temperature
correlation functions vanishes.Comment: 34 pages, 13 figure
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