Unnamed: 0 int64 0 41k | title stringlengths 4 274 | category stringlengths 5 18 | summary stringlengths 22 3.66k | theme stringclasses 8
values |
|---|---|---|---|---|
6,800 | Stable quasicrystalline ground states | cond-mat.stat-mech | We give a strong evidence that noncrystalline materials such as quasicrystals
or incommensurate solids are not exceptions but rather are generic in some
regions of a phase space. We show this by constructing classical lattice-gas
models with translation-invariant, finite-range interactions and with a unique
quasiperiod... | physics |
6,801 | Fractal Dimensions of Confined Clusters in Two-Dimensional Directed Percolation | cond-mat.stat-mech | The fractal structure of directed percolation clusters, grown at the
percolation threshold inside parabolic-like systems, is studied in two
dimensions via Monte Carlo simulations. With a free surface at y=\pm Cx^k and a
dynamical exponent z, the surface shape is a relevant perturbation when k<1/z
and the fractal dimens... | physics |
6,802 | Surface Magnetization of Aperiodic Ising Systems: a Comparative Study of the Bond and Site Problems | cond-mat.stat-mech | We investigate the influence of aperiodic perturbations on the critical
behaviour at a second order phase transition. The bond and site problems are
compared for layered systems and aperiodic sequences generated through
substitution. In the bond problem, the interactions between the layers are
distributed according to ... | physics |
6,803 | Surface Shape and Local Critical Behaviour in Two-Dimensional Directed Percolation | cond-mat.stat-mech | Two-dimensional directed site percolation is studied in systems directed
along the x-axis and limited by a free surface at y=\pm Cx^k. Scaling
considerations show that the surface is a relevant perturbation to the local
critical behaviour when k<1/z where z=\nu_\parallel/\nu is the dynamical
exponent. The tip-to-bulk o... | physics |
6,804 | Anisotropic Scaling in Layered Aperiodic Ising Systems | cond-mat.stat-mech | The influence of a layered aperiodic modulation of the couplings on the
critical behaviour of the two-dimensional Ising model is studied in the case of
marginal perturbations. The aperiodicity is found to induce anisotropic
scaling. The anisotropy exponent z, given by the sum of the surface
magnetization scaling dimens... | physics |
6,805 | Ferromagnetism in Hubbard Models | cond-mat.stat-mech | We present the first rigorous examples of non-singular Hubbard models which
exhibit ferromagnetism at zero temperature. The models are defined in arbitrary
dimensions, and are characterized by finite-ranged hoppings, dispersive bands,
and finite on-site Coulomb interaction U. The picture, which goes back to
Heisenberg,... | physics |
6,806 | Long-range order versus random-singlet phases in quantum antiferromagnetic systems with quenched disorder | cond-mat.stat-mech | The stability of antiferromagnetic long-range order against quenched disorder
is considered. A simple model of an antiferromagnet with a spatially varying
Neel temperature is shown to possess a nontrivial fixed point corresponding to
long-range order that is stable unless either the order parameter or the
spatial dimen... | physics |
6,807 | Breakdown of Landau-Ginzburg-Wilson theory for certain quantum phase transitions | cond-mat.stat-mech | The quantum ferromagnetic transition of itinerant electrons is considered. It
is shown that the Landau-Ginzburg-Wilson theory described by Hertz and others
breaks down due to a singular coupling between fluctuations of the conserved
order parameter. This coupling induces an effective long-range interaction
between the ... | physics |
6,808 | Quantum critical behavior of disordered itinerant ferromagnets | cond-mat.stat-mech | The quantum ferromagnetic transition at zero temperature in disordered
itinerant electron systems is considered. Nonmagnetic quenched disorder leads
to diffusive electron dynamics that induces an effective long-range interaction
between the spin or order parameter fluctuations of the form r^{2-2d}, with d
the spatial d... | physics |
6,809 | Self--organized criticality due to a separation of energy scales | cond-mat.stat-mech | Certain systems with slow driving and avalanche-like dissipation events are
naturally close to a critical point when the ratio of two energy scales is
large. The first energy scale is the threshold above which an avalanche is
triggered, the second scale is the threshold above which a site is affected by
an avalanche. I... | physics |
6,810 | Marginal Anisotropy in Layered Aperiodic Ising Systems | cond-mat.stat-mech | Two-dimensional layered aperiodic Ising systems are studied in the extreme
anisotropic limit where they correspond to quantum Ising chains in a transverse
field. The modulation of the couplings follows an aperiodic sequence generated
through substitution. According to Luck's criterion, such a perturbation
becomes margi... | physics |
6,811 | Minimax Games, Spin Glasses and the Polynomial-Time Hierarchy of Complexity Classes | cond-mat.stat-mech | We use the negative replica method, which was originally developed for the
study of overfrustation in disordered system, to investigate the statistical
behaviour of the cost function of minimax games. These games are treated as
hierarchical statistical mechanical systems, in which one of the components is
at negative t... | physics |
6,812 | From Collapse to Freezing in Random Heteropolymers | cond-mat.stat-mech | We consider a two-letter self-avoiding (square) lattice heteropolymer model
of N_H (out ofN) attracting sites. At zero temperature, permanent links are
formed leading to collapse structures for any fraction rho_H=N_H/N. The average
chain size scales as R = N^{1/d}F(rho_H) (d is space dimension). As rho_H -->
0, F(rho_H... | physics |
6,813 | An extended massless phase and the Haldane phase in a spin-1 isotropic antiferromagnetic chain | cond-mat.stat-mech | We study the phase transition of isotropic spin-1 models in the vicinity of
the Uimin-Lai-Sutherland model by using the SU(3)_1 WZW model with certain
marginal perturbations. The unstable RG trajectory by a marginally relevant
perturbation generates a mass gap for the Haldane phase, and thus the
universality class of t... | physics |
6,814 | Universality properties of the stationary states in the one-dimensional coagulation-diffusion model with external particle input | cond-mat.stat-mech | We investigate with the help of analytical and numerical methods the reaction
A+A->A on a one-dimensional lattice opened at one end and with an input of
particles at the other end. We show that if the diffusion rates to the left and
to the right are equal, for large x, the particle concentration c(x) behaves
like As/x ... | physics |
6,815 | Anisotropic Surface Growth Model in Disordered Media | cond-mat.stat-mech | We introduce a self-organized surface growth model in 2+1 dimensions with
anisotropic avalanche process, which is expected to be in the universality
class of the anisotropic quenched Kardar-Parisi-Zhang equation with alternative
signs of the nonlinear KPZ terms. It turns out that the surface height
correlation function... | physics |
6,816 | Criticality in the two-dimensional random-bond Ising model | cond-mat.stat-mech | The two-dimensional (2D) random-bond Ising model has a novel multicritical
point on the ferromagnetic to paramagnetic phase boundary. This random phase
transition is one of the simplest examples of a 2D critical point occurring at
both finite temperatures and disorder strength. We study the associated
critical properti... | physics |
6,817 | Stochastic Lattice Models with Several Absorbing States | cond-mat.stat-mech | We study two models with n equivalent absorbing states that generalize the
Domany-Kinzel cellular automaton and the contact process. Numerical
investigations show that for n=2 both models belong to the same universality
class as branching annihilating walks with an even number of offspring. Unlike
previously known mode... | physics |
6,818 | Quantum critical behavior of itinerant ferromagnets | cond-mat.stat-mech | The quantum ferromagnetic transition of itinerant electrons is considered. We
give a pedagogical review of recent results which show that zero-temperature
soft modes that are commonly neglected, invalidate the standard
Landau-Ginzburg-Wilson description of this transition. If these modes are taken
into account, then th... | physics |
6,819 | Theory of Branching and Annihilating Random Walks | cond-mat.stat-mech | A systematic theory for the diffusion--limited reaction processes $A + A \to
0$ and $A \to (m+1) A$ is developed. Fluctuations are taken into account via
the field--theoretic dynamical renormalization group. For $m$ even the mean
field rate equation, which predicts only an active phase, remains qualitatively
correct ne... | physics |
6,820 | Surface Critical Behavior of Binary Alloys and Antiferromagnets: Dependence of the Universality Class on Surface Orientation | cond-mat.stat-mech | The surface critical behavior of semi-infinite
(a) binary alloys with a continuous order-disorder transition and
(b) Ising antiferromagnets in the presence of a magnetic field is considered.
In contrast to ferromagnets, the surface universality class of these systems
depends on the orientation of the surface with r... | physics |
6,821 | The duality relation between Glauber dynamics and the diffusion-annihilation model as a similarity transformation | cond-mat.stat-mech | In this paper we address the relationship between zero temperature Glauber
dynamics and the diffusion-annihilation problem in the free fermion case. We
show that the well-known duality transformation between the two problems can be
formulated as a similarity transformation if one uses appropriate (toroidal)
boundary co... | physics |
6,822 | An Analytical and Numerical Study of Optimal Channel Networks | cond-mat.stat-mech | We analyze the Optimal Channel Network model for river networks using both
analytical and numerical approaches. This is a lattice model in which a
functional describing the dissipated energy is introduced and minimized in
order to find the optimal configurations. The fractal character of river
networks is reflected in ... | physics |
6,823 | The Poisson ratio of crystalline surfaces | cond-mat.stat-mech | A remarkable theoretical prediction for a crystalline (polymerized) surface
is that its Poisson ratio (\sigma) is negative. Using a large scale Monte Carlo
simulation of a simple model of such surfaces we show that this is indeed true.
The precise numerical value we find is (\sigma \simeq -0.32) on a (128^2)
lattice at... | physics |
6,824 | Self-organized criticality in a rice-pile model | cond-mat.stat-mech | We present a new model for relaxations in piles of granular material. The
relaxations are determined by a stochastic rule which models the effect of
friction between the grains. We find power-law distributions for avalanche
sizes and lifetimes characterized by the exponents $\tau = 1.53 \pm 0.05$ and
$y = 1.84 \pm 0.05... | physics |
6,825 | Energy avalanches in a rice-pile model | cond-mat.stat-mech | We investigate a one-dimensional rice-pile model. We show that the
distribution of dissipated potential energy decays as a power law with an
exponent $\alpha=1.53$. The system thus provides a one-dimensional example of
self-organized criticality. Different driving conditions are examined in order
to allow for compariso... | physics |
6,826 | Interface roughening with nonlinear surface tension | cond-mat.stat-mech | Using stability arguments, this Brief Report suggests that a term that
enhances the surface tension in the presence of large height fluctuations
should be included in the Kardar-Parisi-Zhang equation. A one-loop
renormalization group analysis then shows for interface dimensions larger than
$\simeq 3.3$ an unstable stro... | physics |
6,827 | A Model for Growth of Binary Alloys with Fast Surface Equilibration | cond-mat.stat-mech | We study a simple growth model for (d+1)-dimensional films of binary alloys
in which atoms are allowed to interact and equilibrate at the surface, but are
frozen in the bulk. The resulting crystal is highly anisotropic: Correlations
perpendicular to the growth direction are identical to a d-dimensional
two-layer system... | physics |
6,828 | Winding Angle Distributions for Directed Polymers | cond-mat.stat-mech | We study analytically and numerically the winding of directed polymers of
length $t$ around each other or around a rod. Unconfined polymers in pure media
have exponentially decaying winding angle distributions, the decay constant
depending on whether the interaction is repulsive or neutral, but not on
microscopic detai... | physics |
6,829 | Matrix Product Eigenstates for One-Dimensional Stochastic Models and Quantum Spin Chains | cond-mat.stat-mech | We show that all zero energy eigenstates of an arbitrary $m$--state quantum
spin chain Hamiltonian with nearest neighbor interaction in the bulk and single
site boundary terms, which can also describe the dynamics of stochastic models,
can be written as matrix product states. This means that the weights in these
states... | physics |
6,830 | Broad Histogram Method | cond-mat.stat-mech | Ferrenberg and Swendsen histogram method is based on Boltzmann probability
distribution which presents exponentially decaying tails. Thus, it gives
accurate measures only within a narrow window around the simulated temperature.
The larger the system, the narrower this window, and the worst the performance
of this metho... | physics |
6,831 | Self similar Barkhausen noise in magnetic domain wall motion | cond-mat.stat-mech | A model for domain wall motion in ferromagnets is analyzed. Long-range
magnetic dipolar interactions are shown to give rise to self-similar dynamics
when the external magnetic field is increased adiabatically. The power spectrum
of the resultant Barkhausen noise is of the form $1/\omega^\alpha$, where
$\alpha\approx 1.... | physics |
6,832 | The asymptotic behaviour of the initially separated A + B(static) -> 0 reaction-diffusion systems | cond-mat.stat-mech | We examine the long-time behaviour of A+B \to 0 reaction-diffusion systems
with initially separated species A and B. All of our analysis is carried out
for arbitrary (positive) values of the diffusion constant D_A of particles A
and initial concentrations a_0 and b_0 of A's and B's. We derive general
formulae for the l... | physics |
6,833 | Exact solution of a one-dimensional continuum percolation model | cond-mat.stat-mech | I consider a one dimensional system of particles which interact through a
hard core of diameter $\si$ and can connect to each other if they are closer
than a distance $d$. The mean cluster size increases as a function of the
density $\rho$ until it diverges at some critical density, the percolation
threshold. This syst... | physics |
6,834 | Some Finite Size Effects in Simulations of Glass Dynamics | cond-mat.stat-mech | We present the results of a molecular dynamics computer simulation in which
we investigate the dynamics of silica. By considering different system sizes,
we show that in simulations of the dynamics of this strong glass former
surprisingly large finite size effects are present. In particular we
demonstrate that the rela... | physics |
6,835 | Roughening Induced Deconstruction in (100) Facets of CsCl Type Crystals | cond-mat.stat-mech | The staggered 6-vertex model describes the competition between surface
roughening and reconstruction in (100) facets of CsCl type crystals. Its phase
diagram does not have the expected generic structure, due to the presence of a
fully-packed loop-gas line. We prove that the reconstruction and roughening
transitions can... | physics |
6,836 | Universal Cubic Eigenvalue Repulsion for Random Normal Matrices | cond-mat.stat-mech | Random matrix models consisting of normal matrices, defined by the sole
constraint $[N^{\dag},N]=0$, will be explored. It is shown that cubic
eigenvalue repulsion in the complex plane is universal with respect to the
probability distribution of matrices. The density of eigenvalues, all
correlation functions, and level ... | physics |
6,837 | Damage spreading and dynamic stability of kinetic Ising models | cond-mat.stat-mech | We investigate how the time evolution of different kinetic Ising models
depends on the initial conditions of the dynamics. To this end we consider the
simultaneous evolution of two identical systems subjected to the same thermal
noise. We derive a master equation for the time evolution of a joint
probability distributi... | physics |
6,838 | Exact and asymtotic formulas for overdamped Brownian dynamics | cond-mat.stat-mech | Exact and asymptotic formulas relating to dynamical correlations for
overdamped Brownian motion are obtained. These formulas include a
generalization of the $f$-sum rule from the theory of quantum fluids, a formula
relating the static current-current correlation to the static density-density
correlation, and an asympto... | physics |
6,839 | Correlated percolation and the correlated resistor network | cond-mat.stat-mech | We present some exact results on percolation properties of the Ising model,
when the range of the percolating bonds is larger than nearest-neighbors. We
show that for a percolation range to next-nearest neighbors the percolation
threshold Tp is still equal to the Ising critical temperature Tc, and present
the phase dia... | physics |
6,840 | Monte-Carlo Simulations of the Dynamical Behavior of the Coulomb Glass | cond-mat.stat-mech | We study the dynamical behavior of disordered many-particle systems with
long-range Coulomb interactions by means of damage-spreading simulations. In
this type of Monte-Carlo simulations one investigates the time evolution of the
damage, i.e. the difference of the occupation numbers of two systems, subjected
to the sam... | physics |
6,841 | Dynamic Critical Phenomena in Channel Flow | cond-mat.stat-mech | A simple model of the driven motion of interacting particles in a two
dimensional random medium is analyzed, focusing on the critical behavior near
to the threshold that separates a static phase from a flowing phase with a
steady-state current. The critical behavior is found to be surprisingly robust,
being independent... | physics |
6,842 | Algebraic and Analytic Properties of the One-Dimensional Hubbard Model | cond-mat.stat-mech | We reconsider the quantum inverse scattering approach to the one-dimensional
Hubbard model and work out some of its basic features so far omitted in the
literature. It is our aim to show that $R$-matrix and monodromy matrix of the
Hubbard model, which are known since ten years now, have good elementary
properties. We p... | physics |
6,843 | Localisation Transition of A Dynamic Reaction Front | cond-mat.stat-mech | We study the reaction-diffusion process $A+B\to \emptyset$ with injection of
each species at opposite boundaries of a one-dimensional lattice and bulk
driving of each species in opposing directions with a hardcore interaction. The
system shows the novel feature of phase transitions between localised and
delocalised rea... | physics |
6,844 | Linear stability analysis of the Hele-Shaw cell with lifting plates | cond-mat.stat-mech | The first stages of finger formation in a Hele-Shaw cell with lifting plates
are investigated by means of linear stability analysis. The equation of motion
for the pressure field (growth law) results to be that of the directional
solidification problem in some unsteady state. At the beginning of lifting the
square of t... | physics |
6,845 | Density Matrix and Renormalization for Classical Lattice Models | cond-mat.stat-mech | We review the variational principle in the density matrix renormalization
group (DMRG) method, which maximizes an approximate partition function within a
restricted degrees of freedom; at zero temperature, DMRG mini- mizes the ground
state energy. The variational principle is applied to two-dimensional (2D)
classical l... | physics |
6,846 | Critical phase of a magnetic hard hexagon model on triangular lattice | cond-mat.stat-mech | We introduce a magnetic hard hexagon model with two-body restrictions for
configurations of hard hexagons and investigate its critical behavior by using
Monte Carlo simulations and a finite size scaling method for discreate values
of activity. It turns out that the restrictions bring about a critical phase
which the us... | physics |
6,847 | Density expansion for transport coefficients: Long-wavelength versus Fermi surface nonanalyticities | cond-mat.stat-mech | The expansion of the conductivity in 2-d quantum Lorentz models in terms of
the scatterer density n is considered. We show that nonanalyticities in the
density expansion due to scattering processes with small and large momentum
transfers, respectively, have different functional forms. Some of the latter
are not logarit... | physics |
6,848 | Comment on "Two Phase Transitions in the Fully frustrated XY Model" | cond-mat.stat-mech | The conclusions of a recent paper by Olsson (Phys. Rev. Lett. 75, 2758
(1995), cond-mat/9506082) about the fully frustrated XY model in two dimensions
are questioned. In particular, the evidence presented for having two separate
chiral and U(1) phase transitions are critically considered. | physics |
6,849 | SU(ν) Generalization of Twisted Haldane-Shastry Model | cond-mat.stat-mech | The SU($\nu$) generalized Haldane-Shastry spin chain with $1/r^2$ interaction
is studied with twisted boundary conditions. The exact wavefunctions of Jastrow
type are obtained for every rational value of the twist angle in unit of
$2\pi$. The spectral flow of the ground state is then discussed as a function
of the twis... | physics |
6,850 | Transport equations including many-particle correlations for an arbitrary quantum system. General formalism | cond-mat.stat-mech | We present a new method to derive transport equations for quantum
many-particle systems. This method uses an equation-of-motion technique and is
applicable to systems with bosons and fermions, arbitrary interactions and
time-dependent external fields. Using a cluster expansion of the r-particle
density matrices the inf... | physics |
6,851 | Improved transport equations including correlations for electron-phonon systems. Comparison with exact solutions in one dimension | cond-mat.stat-mech | We study transport equations for quantum many-particle systems in terms of
correlations by applying the general formalism developed in an earlier paper to
exactly soluble electron-phonon models. The one-dimensional models considered
are the polaron model with a linear energy dispersion for the electrons and a
finite nu... | physics |
6,852 | Simulation studies of fluid critical behaviour | cond-mat.stat-mech | We review and discuss recent advances in the simulation of bulk critical
phenomena in model fluids. In particular we emphasise the extensions to
finite-size scaling theory needed to cope with the lack of symmetry between
coexisting fluid phases. The consequences of this asymmetry for simulation
measurements of quantiti... | physics |
6,853 | A Transfer Matrix study of the staggered BCSOS model | cond-mat.stat-mech | The phase diagram of the staggered six vertex, or body centered solid on
solid model, is investigated by transfer matrix and finite size scaling
techniques. The phase diagram contains a critical region, bounded by a
Kosterlitz-Thouless line, and a second order line describing a deconstruction
transition. In part of the... | physics |
6,854 | The Low-Energy Fixed Points of Random Quantum Spin Chains | cond-mat.stat-mech | The one-dimensional isotropic quantum Heisenberg spin systems with random
couplings and random spin sizes are investigated using a real-space
renormalization group scheme. It is demonstrated that these systems belong to a
universality class of disordered spin systems, characterized by weakly coupled
large effective spi... | physics |
6,855 | Critical Behavior of O(n)-symmetric Systems With Reversible Mode-coupling Terms: Stability Against Detailed-balance Violation | cond-mat.stat-mech | We investigate nonequilibrium critical properties of $O(n)$-symmetric models
with reversible mode-coupling terms. Specifically, a variant of the model of
Sasv\'ari, Schwabl, and Sz\'epfalusy is studied, where violation of detailed
balance is incorporated by allowing the order parameter and the dynamically
coupled conse... | physics |
6,856 | Models of Passive and Reactive Tracer Motion: an Application of Ito Calculus | cond-mat.stat-mech | By means of Ito calculus it is possible to find, in a straight-forward way,
the analytical solution to some equations related to the passive tracer
transport problem in a velocity field that obeys the multidimensional Burgers
equation and to a simple model of reactive tracer motion. | physics |
6,857 | Renormalization of Systems with Non-equilibrium Critical Stationary States | cond-mat.stat-mech | We introduce the general formulation of a renormalization method suitable to
study the critical properties of non-equilibrium systems with steady-states:
the Dynamically Driven Renormalization Group. We renormalize the time evolution
operator by computing the rescaled time transition rate between coarse grained
states.... | physics |
6,858 | Diffusional Relaxation in Random Sequential Deposition | cond-mat.stat-mech | The effect of diffusional relaxation on the random sequential deposition
process is studied in the limit of fast deposition. Expression for the coverage
as a function of time are analytically derived for both the short-time and
long-time regimes. These results are tested and compared with numerical
simulations. | physics |
6,859 | Exact Solution of a Three-Dimensional Dimer System | cond-mat.stat-mech | We consider a three-dimensional lattice model consisting of layers of vertex
models coupled with interlayer interactions. For a particular non-trivial
interlayer interaction between charge-conserving vertex models and using a
transfer matrix approach, we show that the eigenvalues and eigenvectors of the
transfer matrix... | physics |
6,860 | Stationary State Skewness in KPZ Type Growth | cond-mat.stat-mech | Stationary states in KPZ type growth have interesting short distance
properties. We find that typically they are skewed and lack particle-hole
symmetry. E.g., hill-tops are typically flatter than valley bottoms, and all
odd moments of the height distribution function are non-zero. Stationary state
skewness can be turne... | physics |
6,861 | Thermodynamc Approach to Three-Site Antiferromagnetic Ising Model in Chaotic Region | cond-mat.stat-mech | The chaotic properties of the three-site antiferromagnetic Ising model on
Husimi tree are investigated in magnetic field. Macroscopic quantity of
three-site antiferromagnetic Ising model is generated by one dimensional map.
It is shown that in certain parameter setting strange attractors of this map
exhibit multifracta... | physics |
6,862 | Combination of random-barrier and random-trap models | cond-mat.stat-mech | The temperature dependence of the diffusion coefficient of particles is
studied on lattices with disorder. A model is investigated with both trap and
barrier disorder that was introduced before by Limoge and Bocquet (1990 Phys.
Rev. Lett. (65) 60) to explain an Arrhenian temperature-dependence of the
diffusion coeffici... | physics |
6,863 | Forest fires and other examples of self-organized criticality | cond-mat.stat-mech | We review the properties of the self-organized critical (SOC) forest-fire
model. The paradigm of self-organized criticality refers to the tendency of
certain large dissipative systems to drive themselves into a critical state
independent of the initial conditions and without fine-tuning of the
parameters. After an intr... | physics |
6,864 | Coherent propagation of interacting particles in a random potential: the Mechanism of enhancement | cond-mat.stat-mech | Coherent propagation of two interacting particles in $1d$ weak random
potential is considered. An accurate estimate of the matrix element of
interaction in the basis of localized states leads to mapping onto the relevant
matrix model. This mapping allows to clarify the mechanism of enhancement of
the localization lengt... | physics |
6,865 | Density profiles and pair correlation functions of hard spheres in narrow slits | cond-mat.stat-mech | A hard sphere fluid confined by hard, structureless, and parallel walls is
investigated using a certain version of weighted density functional theory. The
density profile, the excess coverage, the finite size contribution to the free
energy, the solvation force, and the total correlation function are determined
as func... | physics |
6,866 | On Critical Exponents and the Renormalization of the Coupling Constant in Growth Models with Surface Diffusion | cond-mat.stat-mech | It is shown by the method of renormalized field theory that in contrast to a
statement based on a mathematically ill-defined invariance transformation and
found in most of the recent publications on growth models with surface
diffusion, the coupling constant of these models renormalizes nontrivially.
This implies that ... | physics |
6,867 | Spin stiffness in the frustrated Heisenberg antiferromagnet | cond-mat.stat-mech | We calculate the spin stiffness of the S=1/2 frustrated Heisenberg
antiferromagnet directly from a general formula which is evaluated in the
Schwinger boson mean-field approximation. Both N\'eel and collinear ordering
are considered. For collinear ordering, we take the anisotropy of this phase
into account, unlike prev... | physics |
6,868 | An efficient implementation of high-order coupled-cluster techniques applied to quantum magnets | cond-mat.stat-mech | We illustrate how the systematic inclusion of multi-spin correlations of the
quantum spin-lattice systems can be efficiently implemented within the
framework of the coupled-cluster method by examining the ground-state
properties of both the square-lattice and the frustrated triangular-lattice
quantum antiferromagnets. ... | physics |
6,869 | Eulerian Walkers as a model of Self-Organised Criticality | cond-mat.stat-mech | We propose a new model of self-organized criticality. A particle is dropped
at random on a lattice and moves along directions specified by arrows at each
site. As it moves, it changes the direction of the arrows according to fixed
rules. On closed graphs these walks generate Euler circuits. On open graphs,
the particle... | physics |
6,870 | Anomalous Height Fluctuation Width in Crossover from Random to Coherent Surface Growths | cond-mat.stat-mech | We study an anomalous behavior of the height fluctuation width in the
crossover from random to coherent growths of surface for a stochastic model. In
the model, random numbers are assigned on perimeter sites of surface,
representing pinning strengths of disordered media. At each time, surface is
advanced at the site ha... | physics |
6,871 | Magnetic and Critical Properties of Alternating Spin Chain with S=1/2,1 in Magnetic Fields | cond-mat.stat-mech | We study an integrable spin chain with an alternating array of spins S=1/2, 1
in external magnetic fields using the Bethe ansatz exact solution. The
calculated magnetization possesses a cusp structure at a critical magnetic
field H=H_{C}, at which the specific heat shows a divergence property. We also
calculate finite-... | physics |
6,872 | Zero-temperature Hysteresis in Random-field Ising Model on a Bethe Lattice | cond-mat.stat-mech | We consider the single-spin-flip dynamics of the random-field Ising model on
a Bethe lattice at zero temperature in the presence of a uniform external
field. We determine the average magnetization as the external field is varied
from minus infinity to plus infinity by setting up the self-consistent field
equations, whi... | physics |
6,873 | Low-Energy Properties of Regularly Depleted Spin Ladders | cond-mat.stat-mech | We investigate a model for the regularly depleted two-leg spin ladder
systems. By using Lieb-Schultz-Mattis theorem, it is rigorously shown that this
model realizes massless excitations or, alternatively, a degenerate ground
state, although the original spin ladder system has a spin gap and a unique
ground state. The g... | physics |
6,874 | Scaling Limit for the Incipient Spanning Clusters | cond-mat.stat-mech | Scaling limits of critical percolation models show major differences between
low and high dimensional models. The article discusses the formulation of the
continuum limit for the former case. A mathematical framework is proposed for
the direct description of the limiting continuum theory. The resulting
structure is exp... | physics |
6,875 | Growth, Percolation, and Correlations in Disordered Fiber Networks | cond-mat.stat-mech | This paper studies growth, percolation, and correlations in disordered fiber
networks. We start by introducing a 2D continuum deposition model with
effective fiber-fiber interactions represented by a parameter $p$ which
controls the degree of clustering. For $p=1$, the deposited network is
uniformly random, while for $... | physics |
6,876 | A Modified Quantum Renormalization Group for xxz Spin Chain | cond-mat.stat-mech | A simple modification of the standard Renormalization Group (RG) technique
for the study of quantum spin systems is introduced. Our method which takes
into account the effect of boundary conditions by employing the concept of
superblock, may be regarded as a simple way for obtaining first estimates of
many properties o... | physics |
6,877 | Spin-Charge Separation, Anomalous Scaling and the Coherence of Hopping in exactly solved Two Chain Models | cond-mat.stat-mech | The coherence of transport between two one-dimensional interacting Fermi
liquids, coupled by single particle hopping and interchain interaction, is
examined in the context of two exactly soluble models. It is found that the
coherence of the inter-chain hopping depends on the interplay between
inter-chain hopping and in... | physics |
6,878 | Dynamic correlations of antiferromagnetic spin-1/2 XXZ chains at arbitrary temperature from complete diagonalization | cond-mat.stat-mech | All eigenstates and eigenvalues are determined for the spin- 1/2 $XXZ$ chain
$H = 2J \sum_i ( S_{i}^{x} S_{i + 1}^{x} + S_{i}^{y} S_{i + 1}^{y} + \Delta
S_i^z S_{i + 1}^{z})$ for rings with up to N=16 spins, for anisotropies
$\Delta=0 , \cos(0.3\pi)$, and 1. The dynamic spin pair correlations $<
S_{l+n}^{\mu}(t) S_l^{\... | physics |
6,879 | An Objective Definition of Damage Spreading - Application to Directed Percolation | cond-mat.stat-mech | We present a general definition of damage spreading in a pair of models.
Using this general framework, one can define damage spreading in an objective
manner, that does not depend on the particular dynamic procedure that is being
used. The formalism is applied to the Domany-Kinzel cellular automaton in one
dimension; t... | physics |
6,880 | Critical holes in undercooled wetting layers | cond-mat.stat-mech | The profile of a critical hole in an undercooled wetting layer is determined
by the saddle-point equation of a standard interface Hamiltonian supported by
convenient boundary conditions. It is shown that this saddle-point equation can
be mapped onto an autonomous dynamical system in a three-dimensional phase
space. The... | physics |
6,881 | Schwinger-boson approach to quantum spin systems: Gaussian fluctuactions in the "natural" gauge | cond-mat.stat-mech | We compute the Gaussian-fluctuation corrections to the saddle-point
Schwinger-boson results using collective coordinate methods. Concrete
application to investigate the frustrated J1-J2 antiferromagnet on the square
lattice shows that, unlike the saddle-point predictions, there is a quantum
nonmagnetic phase for 0.53 <... | physics |
6,882 | Critical Properties of gapped spin-1/2 chains and ladders in a magnetic field | cond-mat.stat-mech | An interesting feature of spin-1/2 chains with a gap is that they undergo a
commensurate-incommensurate transition in the presence of an external magnetic
field $H$. The system is in a gapless incommensurate regime for all values of
the magnetic field between the lower critical field $H_{c1}$ and an upper
critical fiel... | physics |
6,883 | Heisenberg model with Dzyaloshinskii-Moriya interaction: A Schwinger boson study | cond-mat.stat-mech | We present a Schwinger-boson approach to the Heisenberg model with
Dzyaloshinskii-Moriya interaction. We write the anisotropic interactions in
terms of Schwinger bosons keeping the correct symmetries present in the spin
representation, which allows us to perform a conserving mean-field
approximation. Unlike previous st... | physics |
6,884 | Quantum Renormalization Group for 1 Dimensional Fermion Systems | cond-mat.stat-mech | Inspired by the superblock method of White, we introduce a simple
modification of the standard Renormalization Group (RG) technique for the study
of quantum lattice systems. Our method which takes into account the effect of
Boundary Conditions(BC), may be regarded as a simple way for obtaining first
estimates of many p... | physics |
6,885 | Reentrant Wetting Transition of a Rough Wall | cond-mat.stat-mech | A $2D$ model describing depinning of an interface from a rough, self-affine
substrate, is studied by transfer matrix methods. The phase diagram is
determined for several values of the roughness exponent, $\zeta_S$, of the
attractive wall. For all $\zeta_S>0$ the following scenario is observed. In
first place, in contra... | physics |
6,886 | Deterministic Exclusion Process with a Stochastic Defect: Matrix-Product Ground States | cond-mat.stat-mech | We study a one-dimensional anisotropic exclusion model describing particles
moving deterministically on a ring with a single defect across which they move
with probability 0 < q < 1. We show that the stationary state of this model can
be represented as a matrix-product state. | physics |
6,887 | Generalized gradient expansions in quantum transport equations | cond-mat.stat-mech | Gradient expansions in quantum transport equations of a Kadanoff-Baym form
have been reexamined. We have realized that in a consistent approach the
expansion should be performed also inside of the self-energy in the scattering
integrals of these equations. In the first perturbation order this internal
expansion gives n... | physics |
6,888 | Generalization of the Mean-Field Ising Model Within Tsallis Thermostatistics | cond-mat.stat-mech | In this study, the mean-field Ising model, using the Bogolyubov inequality
which has been obtained in the frame of the generalized statistics, has been
investigated. | physics |
6,889 | Exact results for one dimensional stochastic cellular automata for different types of updates | cond-mat.stat-mech | We study two common types of time-noncontinuous updates for one dimensional
stochastic cellular automata with arbitrary nearest neighbor interactions and
arbitrary open boundary conditions. We first construct the stationary states
using the matrix product formalism. This construction then allows to prove a
general conn... | physics |
6,890 | Critical behaviour of the dilute O(n), Izergin-Korepin and dilute $A_L$ face models: Bulk properties | cond-mat.stat-mech | The analytic, nonlinear integral equation approach is used to calculate the
finite-size corrections to the transfer matrix eigen-spectra of the critical
dilute O(n) model on the square periodic lattice. The resulting bulk conformal
weights extend previous exact results obtained in the honeycomb limit and
include the ne... | physics |
6,891 | Blume-Emery-Griffiths model on the square lattice with repulsive biquadratic coupling | cond-mat.stat-mech | Using a real-space renormalization group procedure with no adjustable
parameters, we investigate the Blume-Emery-Griffiths model on the square
lattice. The formalism respects sublattice symmetry, allowing the study of both
signs of K, the biquadratic exchange coupling. Our results for K>0 are compared
with other renorm... | physics |
6,892 | Spectra of non-hermitian quantum spin chains describing boundary induced phase transitions | cond-mat.stat-mech | The spectrum of the non-hermitian asymmetric XXZ-chain with additional
non-diagonal boundary terms is studied. The lowest lying eigenvalues are
determined numerically. For the ferromagnetic and completely asymmetric chain
that corresponds to a reaction-diffusion model with input and outflow of
particles the smallest en... | physics |
6,893 | Inhomogeneous Reptation of Polymers | cond-mat.stat-mech | We study the motion of long polymers (eg DNA) in a gel under the influence of
an external force acting locally on small segments of the polymer. In
particular, we examine the dependence of the drift velocity on the position
where the force acts and the length of the polymer. As an application, we
discuss the possibilit... | physics |
6,894 | Thermodynamic Properties of a Trapped Interacting Bose Gas | cond-mat.stat-mech | A Bose gas in an external potential is studied by means of the local density
approximation. Analytical results are derived for the thermodynamic properties
of an ideal Bose gas in a generic power-law trapping potential, and their
dependence on the mutual interaction of atoms in the case of a non-ideal Bose
gas. | physics |
6,895 | On the low-temperature phase of the three-state antiferromagnetic Potts model on the simple cubic lattice | cond-mat.stat-mech | The three-state antiferromagnetic Potts model on the simple cubic lattice is
investigated using the cluster variation method in the cube and the star-cube
approximations. The broken-sublattice-symmetry phase is found to be stable in
the whole low-temperature region, contrary to previous results obtained using a
modifie... | physics |
6,896 | Surface Incommensurate Structure in an Anisotropic Model with competing interactions on Semiinfinite Triangular Lattice | cond-mat.stat-mech | An anisotropic spin model on a triangular semiinfinite lattice with
ferromagnetic nearest-neighbour interactions and one antiferromagnetic
next-nearest-neighbour interaction is investigated by the cluster
transfer-matrix method. A phase diagram with <2> antiphase, ferromagnetic,
incommensurate, and disordered phase is ... | physics |
6,897 | The three species monomer-monomer model: A mean-field analysis and Monte Carlo study | cond-mat.stat-mech | We study the phase diagram and critical behavior of a one dimensional three
species monomer-monomer surface reaction model. Static Monte Carlo simulations
show a phase diagram consisting of a reactive steady state bordered by three
equivalent unreactive phases where the surface is saturated with one monomer
species. Th... | physics |
6,898 | Universal fluctuations in the support of the random walk | cond-mat.stat-mech | A random walk starts from the origin of a d-dimensional lattice. The
occupation number n(x,t) equals unity if after t steps site x has been visited
by the walk, and zero otherwise. We study translationally invariant sums M(t)
of observables defined locally on the field of occupation numbers. Examples are
the number S(t... | physics |
6,899 | Generalized Distribution Functions and an Alternative Approach to Generalized Planck Radiation Law | cond-mat.stat-mech | In this study, recently introduced generalized distribution functions are
summarized and by using one of these distribution functions, namely generalized
Planck distribution, an alternative approach to the generalized Planck law for
the blackbody radiation has been tackled. | physics |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.