January 2005 arXiv papers — page 14
Showing 1,301–1,400 of 3,506 papers
Unconditional fidelity thresholds in single copy distillation and some aspects of quantum error correction
quant-phPawel Horodecki, Maciej Demianowicz
Various aspects of distillation of noisy entanglement and some associated effects in quantum error correction are considered. In particular we prove that if only one--way classical communication (from Alice to Bob) is allowed and the shared $d \otimes d$ state is not pure then there is a threshold for optimal entanglement fraction $F$ of the state (being an
Ophir Flomenbom, Joseph Klafter
Trajectories of on-off events are the output of many single molecule experiments. Usually, one describes the underlying mechanism that generates the trajectory using a kinetic scheme, and by analyzing the trajectory aims at deducing this scheme. In a previous work [O. Flomenbom, J. Klafter, and A. Szabo, submitted (2004)], we showed that when successive even
R. C. Nazzario, T. W. Hyde
Observations of the Kuiper Belt indicate that a larger than expected percentage of KBO's (approximately 8 out of 500) are in binary pairs. The formation and survival of such objects presents a conundrum [1]. Two competing theories have been postulated to try to solve this problem. One entails the physical collision of bodies [2] while the other utilizes
Electron Photodetachment from Aqueous Anions. III. Dynamics of Geminate Pairs Derived from Photoexcitation of Mono- vs. Poly- atomic Anions
physics.chem-phRui Lian, Dmitri A. Oulianov, Robert A. Crowell, Ilya A. Shkrob
Photostimulated electron detachment from aqueous inorganic anions is the simplest example of solvent-mediated electron transfer. Here we contrast the behavior of halide anions with that of small polyatomic anions, such as pseudohalide anions (e.g., HS-) and common polyvalent anions (e.g., SO32-). Geminate recombination dynamics of hydrated electrons generate
Lorenzo J. Curtis, David G. Ellis
A simple position probability density formulation is presented for the motion of a particle in a spherically symmetric potential. The approach provides an alternative to Newtonian methods for presentation in an elementary course, and requires only elementary algebra and one tabulated integral. The method is applied to compute the distributions for the Kepler
Lukasz Cwiklik, Barbara Jagoda-Cwiklik, Marek Frankowicz
The kinetics of a 2A + B2 = 2AB reaction on supported metal catalyst with spillover effects is investigated using Dynamic Monte Carlo simulations. In the presented model A particles can adsorb reversibly on both metal clusters and the support whereas B2 particles can adsorb dissociatively only on metal clusters. Particles A can diffuse from the support to me
K. Kaneko, R. F. Casten, M. Hasegawa, T. Mizusaki
A study of the energies of the first excited $0^+$ states in all even-even $Z$ $\geq$ 8 nuclei reveals an anomalous behavior in some nuclei with $N$ = $Z$, $Z$ $\pm$ 2. We analyze these irregularities in the framework of the shell model. It is shown that proton-neutron correlations play an important role in this phenomenon.
Andrea Meucci, Carlotta Giusti, Franco Davide Pacati
A relativistic Green's function and a distorted-wave impulse-approximation approach to charged- and neutral-current neutrino-nucleus quasielastic scattering are developed. Results for the neutrino (antineutrino) reactions on $^{16}$O and $^{12}$C target nuclei are presented and discussed.
Relativistic Green's function approach to parity-violating quasielastic electron scattering
nucl-thAndrea Meucci, Carlotta Giusti, Franco Davide Pacati
A relativistic Green's function approach to parity-violating quasielastic electron scattering is presented. The components of the hadron tensor are expressed in terms of the single particle Green's function, which is expanded in terms of the eigenfunctions of the non-Hermitian optical potential, in order to account for final state interactions withou
I. Borbély
The formulation of the eigenvalue problem for the Schrödinger equation is studied, for the numerical solution a new approach is applied. With the usual exponentially rising free-state asymptotical behavior, and also with a first order correction to it, the lower half of the $k$ plane is systematically explored. Note that no other method, including the comple
V. Punjabi, C. F. Perdrisat
The ratio of the proton elastic electromagnetic form factors, $G_{Ep}/G_{Mp}$, was obtained by measuring $P_{t}$ and $P_{\ell}$, the transverse and longitudinal recoil proton polarization components, respectively, for the elastic $\vec e p \to e\vec p$ ~reaction in the four-momentum transfer squared range of 0.5 to 3.5 GeV$^2$. In the single-photon exchange
J. E. Nelson, R. F. Picken
We describe some results concerning the phase space of 3-dimensional Einstein gravity when space is a torus and with negative cosmological constant. The approach uses the holonomy matrices of flat SL(2,R) connections on the torus to parametrise the geometry. After quantization, these matrices acquire non-commuting entries, in such a way that they satisfy q-c
Shantala Mukherjee
A complete description of the coadjoint orbits for A_{n-1}^{+}, the nilpotent Lie algebra of n-by-n strictly upper triangular matrices, has not yet been obtained, though there has been steady progress on it ever since the orbit method was devised. We apply methods developed by Andre' to find defining equations for the elementary coadjoint orbits for the
Boris Plotkin, Grigori Zhitomirski
Given a variety of universal algebras. A method is suggested for describing automorphisms of a category of free algebras of this variety. Applying this general method all automorphisms of such categories are found in two cases: 1) for the variety of all free associative K-algebras over an infinite field K and 2) for the variety of all representations of grou
Guyan Robertson
Let $(G,{\mathfrak I},N,S)$ be an affine topological Tits system, and let $Γ$ be a torsion free cocompact lattice in $G$. This article studies the coinvariants $H_0(Γ; C(Ω,{\mathbb Z}))$, where $Ω$ is the Furstenberg boundary of $G$. It is shown that the class $[1]$ of the identity function in $H_0(Γ; C(Ω,{\mathbb Z}))$ has finite order, with explicit bounds
Atanas Iliev, Laurent Manivel
We study the varieties of reductions associated to the variety of rank one matrices in $\fgl\_n$. These varieties are defined as natural compactifications of the different ways to write the identity matrix as a sum of $n$ rank one matrices. Equivalently, they compactify the quotient of $PGL\_n$ by the normalizer of a maximal torus. In particular, we prove th
Allan Pinkus
Approximation theory is concerned with the ability to approximate functions by simpler and more easily calculated functions. The first question we ask in approximation theory concerns the {\it possibility of approximation}. Is the given family of functions from which we plan to approximate dense in the set of functions we wish to approximate? In this work we
Francisco Balibrea, Orlando Freitas, Jose Sousa Ramos
The purpose of this paper is to study some properties of the Newton maps associated to real quintic polynomials. First using the Tschirnhaus transformation, we reduce the study of Newton's method for general quintic polynomials to the case $f(x)=x^{5}-c x+1$. Then we use symbolic dynamics to consider this last case and construct a kneading sequences tree
Friedrich Wehrung
We find a distributive (v, 0, 1)-semilattice S of size $ aleph\_1$ that is not isomorphic to the maximal semilattice quotient of any Riesz monoid endowed with an order-unit of finite stable rank. We thus obtain solutions to various open problems in ring theory and in lattice theory. In particular: - There is no exchange ring (thus, no von Neumann regular rin
Friedrich Wehrung
Various embedding problems of lattices into complete lattices are solved. We prove that for any join-semilattice S with the minimal join-cover refinement property, the ideal lattice IdS of S is both algebraic and dually algebraic. Furthermore, if there are no infinite D-sequences in J(S), then IdS can be embedded into a direct product of finite lower bounded
Friedrich Wehrung, Marina V. Semenova
For a left vector space V over a totally ordered division ring F, let Co(V) denote the lattice of convex subsets of V. We prove that every lattice L can be embedded into Co(V) for some left F-vector space V. Furthermore, if L is finite lower bounded, then V can be taken finite-dimensional, and L embeds into a finite lower bounded lattice of the form $Co(V,Z)
G. Stojanovic, S. Tabachnikov
A manifold is T-embedded into an affine space if its tangent spaces at distinct points are disjoint. We prove that an n-dimensional disc cannot be T-embedded into 2n-dimensional space.
Luc Robbiano, Claude Zuily
We prove the (local in time) Strichartz estimates (for the full range of parameters given by the scaling unless the end point) for asymptotically flat and non trapping perturbations of the flat Laplacian in $\R^n$, $n\geq 2$. The main point of the proof, namely the dispersion estimate, is obtained in constructing a parametrix. The main tool for this construc
Vassily Olegovich Manturov
In the present paper, we construct the Khovanov homology theory for virtual links. Besides the direct approach with Z_{2} coefficients we also describe the Khovanov homology for framed links and the Khovanov homology using ``double cover''. The latter two approaches are based on the notion of ``atom''.
Kenichiro Tanabe
Let V be a simple vertex operator algebra and G a finite automorphism group. We give a construction of intertwining operators for irreducible V^G-modules which occur as submodules of irreducible V-modules by using intertwining operators for V. We also determine some fusion rules for a vertex operator algebra as an application.
D. Burns, V. Guillemin, E. Lerman
We generalize a theorem of Delzant classifying compact connected symplectic manifolds with completely integrable torus actions to certain singular symplectic spaces. The assumption on singularities is that if they are not finite quotient then they are isolated.
K. A. Brown, K. R. Goodearl, M. Yakimov
The standard Poisson structure on the rectangular matrix variety M_{m,n}(C) is investigated, via the orbits of symplectic leaves under the action of the maximal torus T of GL_{m+n}(C). These orbits, finite in number, are shown to be smooth irreducible locally closed subvarieties of M_{m,n}(C), isomorphic to intersections of dual Schubert cells in the full fl
Andrea Malchiodi
We prove compactness of solutions to some fourth order equations with exponential nonlinearities on four manifolds. The proof is based on a refined bubbling analysis, for which the main estimates are given in integral form. Our result is used in a subsequent paper to find critical points (via minimax arguments) of some geometric functional, which give rise t
Jiang-Hua Lu, Milen Yakimov
We study a class of double coset spaces R_A \backslash G_1 \times G_2 /R_C, where G_1 and G_2 are connected reductive algebraic groups, and R_A and R_C are certain spherical subgroups of G_1 \times G_2 obtained by ``identifying'' Levi factors of parabolic subgroups in G_1 and G_2. Such double cosets naturally appear in the symplectic leaf decompositi
Tobias Reichenbach
We study quantized equations of motion and currents, that means equations on the level of Green's functions, in three different approaches to noncommutative quantum field theories. At first, the case of only spatial noncommutativity is investigated in which the modified Feynman rules can be applied. The classical equations of motion and currents are foun
Thibault Damour
This review is made of two parts which are related to Poincaré in different ways. The first part reviews the work of Poincaré on the Theory of (Special) Relativity. One emphasizes both the remarkable achievements of Poincaré, and the fact that he never came close to what is the essential conceptual achievement of Einstein: changing the concept of time. The s
Kasper Peeters, Jan Plefka, Marija Zamaklar
We review a study of the semiclassical decay of macroscopic spinning strings in AdS_5 x S^5 as well as its dual gauge theory description. The conservation of the infinite tower of commuting charges in the semiclassical string sigma-model description of the process suggests that the decay channel of maximal probability should preserve integrability in the gau
Thomas Mohaupt, Frank Saueressig
We discuss the extension of our recent work hep-th/0410272, hep-th/0410273 to general conifold transitions and type-IIA string theory.
Jnanadeva Maharana
We consider NSR superstring in AdS_3 X S_3 X R_4 background. The action is expressed in terms of the variables on the group manifolds SL(2,R) and SU(2) as 1+1 dimensional sigma models with Wess-Zumino terms, associated with AdS_3 and S_3 respectively. R_4 is flat Euclidean space. We show the existence of classical nonlocal conserved currents in the superspac
Myron Bander
Coordinate noncommutativity, rather than being introduced through deformations of operator products, is achieved by coupling an auxiliary system with large energy excitations to the one of interest. Integrating out the auxiliary dynamics, or equivalently taking ground state expectation values, leads to the desired coordinate noncommutativity. The product res
Gia Dvali, Michele Papucci, Matthew D. Schwartz
We study a modification of electromagnetism which violates Lorentz invariance at large distances. In this theory, electromagnetic waves are massive, but the static force between charged particles is Coulomb not Yukawa. At very short distances the theory looks just like QED. But for distances larger than 1/m the massive dispersion relation of the waves can be
A. Sagnotti, E. Sezgin, P. Sundell
We report on an analysis of the Vasiliev construction for minimal bosonic higher-spin master fields with oscillators that are vectors of SO(D-1,2) and doublets of Sp(2,R). We show that, if the original master field equations are supplemented with a strong Sp(2,R) projection of the 0-form while letting the 1-form adjust to the resulting Weyl curvatures, the l
Lon-chang Liu
The commonly used $γ_μ} Pomeron-quark coupling changes its sign under charge conjugation, in contradiction to the property of Pomeron. I show that the Pomeron-quark coupling is tensorial and is invariant under the charge conjugation.
Sabine Jeschonnek, J. W. Van Orden
We apply a model for the study of quark-hadron duality in inclusive electron scattering to the calculation of spin observables. The model is based on solving the Dirac equation numerically for a scalar confining linear potential and a vector color Coulomb potential. We qualitatively reproduce the features of quark-hadron duality for all potentials considered
E. Iancu, D. N. Triantafyllopoulos
In a previous publication, we have constructed a set of non-linear evolution equations for dipole scattering amplitudes in QCD at high energy, which extends the Balitsky-JIMWLK hierarchy by including the effects of fluctuations in the gluon number in the target wavefunction. In doing so, we have relied on the color dipole picture, valid in the limit where th
Huan Z. Huang, Johann Rafelski
We discuss experimental features of identified particle production from nucleus-nucleus collisions. These features reflect hadronization from a deconfined partonic matter whose particle formation scheme is distinctly different from fragmentation phenomenology in elementary collisions. Multi-parton dynamics, such as quark coalescences or recombinations, appea
Chong-Xing Yue, Lei Wang, Jian-Xing Chen
In the context of the littlest Higgs$(LH)$ model, we study the process $ e^{+}e^{-}\to t\bar{t}$. We find that the new gauge bosons $Z_{H}$ and $B_{H}$ can produce significant correction effects on this process, which can be further enhanced by the suitably polarized beams. In most of the parameter space preferred by the electroweak precision data, the absol
Ariel R. Zhitnitsky
The main leitmotiv of the present talk is analysis of different topological objects such as strings and domain walls in QCD. As it is well known, the standard model in general (and QCD in particular) does not support any kind of such objects due to some simple topological arguments. However, the situation cardinally changes when one considers QCD in large $N
Breese Quinn
Recent performance of Fermilab's Tevatron has exceeded this year's design goals and further accelerator upgrades are underway. The high-luminosity period which follows these improvements is known as Run IIb. The D0 experiment is in the midst of a comprehensive upgrade program designed to enable it to thrive with much higher data rate and occupancy. E
C. Aidala
In late 2001 the first polarized proton collisions at the Relativistic Heavy Ion Collider (RHIC) took place. The PHENIX experiment at RHIC has a broad program to investigate the spin structure of the proton. This program will be described, and first results will be presented.
David W. Hertzog
Our recent series of measurements at Brookhaven National Laboratory determined the muon anomalous magnetic moment \amu to a precision of 0.5 ppm. The final result--representing the average of five running periods using both positive and negative muons--is $\amu ^\pm = 11 659 208(6) \times 10^{-10}$. It lies 2.7 standard deviations above the standard model ex
L. Favart
A review is given of the measurements of the hard diffractive interactions in recent years from two high-energy colliders, the HERA $ep$ collider and the Tevatron $p\bar{p}$ collider. The structure of the diffractive exchange in terms of partons, the factorisation properties and the ratio of diffractive to non-diffractive cross sections are discussed.
Krzysztof Kurek
Measurements of the longitudinal spin cross section asymmetry for deep inelastic muon-nucleon interactions with two high transverse momentum hadrons ($p_T >$ 0.7 GeV) in the final state are presented for SMC data for polarized proton and deuteron and for data on polarized deuteron from COMPASS taken in 2002 and 2003. The muon asymmetries determined with a cu
M. Zavertyaev
A simple example of the kinematic reflection in the $D^*p$ system at about 3.1 GeV/c^2 is given.
Thibault Damour
The structure of the general, inhomogeneous solution of (bosonic) Einstein-matter systems in the vicinity of a cosmological singularity is considered. We review the proof (based on ideas of Belinskii-Khalatnikov-Lifshitz and technically simplified by the use of the Arnowitt-Deser-Misner Hamiltonian formalism) that the asymptotic behaviour, as one approaches
Global existence and future asymptotic behaviour for solutions of the Einstein-Vlasov-scalar field system with surface symmetry
gr-qcDavid Tegankong
We prove in the cases of plane and hyperbolic symmetries a global in time existence result in the future for comological solutions of the Einstein-Vlasov-scalar field system, with the sources generated by a distribution function and a scalar field, subject to the Vlasov and wave equations respectively. The spacetime is future geodesically complete in the spe
R. J. Adler, J. M. Overduin
We study here what it means for the Universe to be nearly flat, as opposed to exactly flat. We give three definitions of nearly flat, based on density, geometry and dynamics; all three definitions are equivalent and depend on a single constant flatness parameter epsilon that quantifies the notion of nearly flat. Observations can only place an upper limit on
Kenneth L. Clarkson, Kasturi Varadarajan
Given a collection S of subsets of some set U, and M a subset of U, the set cover problem is to find the smallest subcollection C of S such that M is a subset of the union of the sets in C. While the general problem is NP-hard to solve, even approximately, here we consider some geometric special cases, where usually U = R^d. Extending prior results, we show
Alexander Haubold, John R. Kender
We investigate methods of segmenting, visualizing, and indexing presentation videos by separately considering audio and visual data. The audio track is segmented by speaker, and augmented with key phrases which are extracted using an Automatic Speech Recognizer (ASR). The video track is segmented by visual dissimilarities and augmented by representative key
Two Iterative Algorithms for Solving Systems of Simultaneous Linear Algebraic Equations with Real Matrices of Coefficients
math.NAA. S. Kondratiev, N. P. Polishchuk
The paper describes two iterative algorithms for solving general systems of M simultaneous linear algebraic equations (SLAE) with real matrices of coefficients. The system can be determined, underdetermined, and overdetermined. Linearly dependent equations are also allowed. Both algorithms use the method of Lagrange multipliers to transform the original SLAE
A. Y. Dokow H. Vilchik, A. Frydman
We have performed magnetoresistance (MR) measurements of granular ferromagnets having lateral dimensions smaller than 0.5 $μ$m and containing a small number of grains (down to about 100). Compared to macroscopic samples, these granular samples exhibit unusually large saturation fields and MR amplitudes. In addition, the evolution of the magnetoresistance cur
Tatsuya Yanagisawa, Terutaka Goto, Yuichi Nemoto, Ryuta Watanuki
The magnetic phase diagram for antiferro-quadrupole (AFQ) ordering in tetragonal HoB$_2$C$_2$ has been investigated by measurements of elastic constants $C_{11}$, $C_{44}$ and $C_{66}$ in fields along the basal $x$-$y$ plane as well as the principal [001]-axis. The hybrid magnet (GAMA) in Tsukuba Magnetic Laboratory was employed for high field measurements u
B. A. Turek, K. W. Lehnert, A. Clerk, D. Gunnarsson
We report an experimental observation of the backaction of a Single Electron Transistor (SET) measuring the Coulomb staircase of a single electron box. As current flows through the SET, the charge state of the SET island fluctuates. These fluctuations capacitively couple to the box and cause changes in the position, width, and asymmetry of the Coulomb stairc
Analytical procedure to determine the self-referred lacunarity function for simple shapes. Supplementary material
cond-mat.stat-mechErbe P. Rodrigues, Marconi. S. Barbosa, Luciano da F. Costa
The analytical calculation of the self-referred lacunarity is used as a validation standard of the computational algorithm. In this supplementary material to our article (see cond-mat/0407079) we present a detailed calculation for two simple shapes, namely a square box and a cross.
Evolution of Mid-gap States and Residual 3-Dimensionality in La$_{2-x}$Sr$_x$CuO$_4$
cond-mat.supr-conS. Sahrakorpi, M. Lindroos, R. S. Markiewicz, A. Bansil
We have carried out extensive first principles doping-dependent computations of angle-resolved photoemission (ARPES) intensities in La$_{2-x}$Sr$_x$CuO$_4$ (LSCO) over a wide range of binding energies. Intercell hopping and the associated 3-dimensionality, which is usually neglected in discussing cuprate physics, is shown to play a key role in shaping the AR
I. Bena, R. Kawai, C. Van den Broeck, Katja Lindenberg
Stochastic Stokes' drift and hypersensitive transport driven by dichotomous noise are theoretically investigated. Explicit mathematical expressions for the asymptotic probability density and drift velocity are derived including the situation in which particles cross unstable fixed points. The results are confirmed by numerical simulations.
Christian D. Santangelo
By decomposing the Coulomb interaction into a long distance component appropriate for mean-field theory, and a nonmean-field short distance component, we compute the counterion density near a charged surface for all values of the counterion coupling parameter. A modified strong-coupling expansion that is manifestly finite at all coupling strengths is used to
S. Denisov, S. Flach, A. Gorbach
We study the mechanism of directed energy transport for soliton ratchets. The energy flow appears due to the progressive motion of a soliton (kink) which is an energy carrier. However, the energy current formed by internal system deformations (the total field momentum) is zero. We solve the underlying puzzle by showing that the energy flow is realized via an
Umberto Balucani, Luca Capriotti, Alessandro Cuccoli, Andrea Fubini
Over the years the research group in Firenze has produced a number of theoretical results concerning the statistical mechanics of quantum antiferromagnetic models, which range from the theory of two-magnon Raman scattering to the characterization of the phase transitions in quantum low-dimensional antiferromagnetic models. Our research activity was steadily
Denis Danilov, Britta Nestler
The evolution of solidification microstructures in ternary metallic alloys is investigated by adaptive finite element simulations of a general multicomponent phase-field model. A morphological transition from dendritic to globular growth is found by varying the alloy composition at a fixed undercooling. The dependence of the growth velocity and of the impuri
Efficient evaluation of partition functions of frustrated and inhomogeneous spin systems
cond-mat.otherV. Murg, F. Verstraete, J. I. Cirac
We present a numerical method to evaluate partition functions and associated correlation functions of inhomogeneous 2--D classical spin systems and 1--D quantum spin systems. The method is scalable and has a controlled error. We illustrate the algorithm by calculating the finite--temperature properties of bosonic particles in 1--D optical lattices, as realiz
Carbon doped symmetric GaAs/AlGaAs quantum wells with hole mobilities beyond 10^6 cm^2/Vs
cond-mat.mes-hallC. Gerl, S. Schmult, H. - P. Tranitz, C. Mitzkus
Utilizing a novel carbon doping source, we prepared two-dimensional hole gases in a symmetric quantum well structure in the GaAs/AlGaAs heterosystem. Low temperature hole mobilities up to 1.2 x 10^6 cm^2/Vs at a density of 2.3 x 10^11 cm^-2 were achieved on GaAs (001) substrates. In contrast to electron systems, the hole mobility sensitively depends on varia
Hirofumi Wada
On the basis of a hydrodynamical model analogous to that in critical fluids, we investigate the influences of shear flow upon the electrostatic contribution to the viscosity of binary electrolyte solutions in the Debye-Hückel approximation. Within the linear-response theory, we reproduce the classical limiting law that the excess viscosity is proportional to
V. R. Palkar, S. K. Malik
The coexistence of ferroelectric and ferromagnetic properties at room temperature is very rarely observed. We have been successful in converting ferroelectric PbTiO3 into a magnetoelectric material by partly substituting Fe at the Ti site. The Pb(Fe1-xTix)O3 system exhibits ferroelectric and ferromagnetic ordering at room temperature. Even more remarkably, o
A. Baldassarri, A. Barrat, G. D'Anna, V. Loreto
In this paper we discuss whether thermodynamical concepts and in particular the notion of temperature could be relevant for the dynamics of granular systems. We briefly review how a temperature-like quantity can be defined and measured in granular media in very different regimes, namely the glassy-like, the liquid-like and the granular gas. The common denomi
Metal-insulator transition in PrRu$_4$P$_{12}$ and SmRu$_4$P$_{12}$ investigated by optical spectroscopy
cond-mat.str-elM. Matsunami, L. Chen, M. Takimoto, H. Okamura
Electronic structures of the filled-skutterudite compounds PrRu$_4$P$_{12}$ and SmRu$_4$P$_{12}$, which undergo a metal-insulator transition (MIT) at $T_{\rm MI}$ = 60 K and 16 K, respectively, have been studied by means of optical spectroscopy. Their optical conductivity spectra develop an energy gap of $\sim$ 10 meV below $T_{\rm MI}$. The observed charact
The possible origin of the higher magnetic phase transition in RuSr2Eu1.5Ce0.5Cu2O10 (Ru-1222)
cond-mat.supr-conI. Felner, E. Galstyan, I. Nowik
Two magnetic transitions are observed in the magneto-superconducting RuEu2-xCexSr2Cu2O10 (Ru-1222), at TM 160 K and TM2~80 K. Below TM2 the Ru moments are weak-ferromagnetically ordered and wide ferromagnetic hysteresis loops are observed, they become narrow and disappear at ~ 60-70 K. Above TM2, (i) small antiferromagnetic-like hysteresis loops reappear wit
Electron spin resonance in the $S$=1/2 quasi-one-dimensional antiferromagnet with Dzyaloshinskii-Moriya interaction BaCu$\_2$Ge$\_2$O$\_7$
cond-mat.str-elSylvain Bertaina, V. A. Pashchenko, Anatoli Stepanov, T. Masuda
We have investigated the electron spin resonance (ESR) on single crystals of BaCu$\_2$Ge$\_2$O$\_7$ at temperatures between 300 and 2 K and in a large frequency band, 9.6 -134 GHz, in order to test the predictions of a recent theory, proposed by Oshikawa and Affleck (OA), which describes the ESR in a $S$=1/2 Heisenberg chain with the Dzyaloshinskii-Moriya in
P. Pureur, F. Wolff Fabris, J. Schaf, V. N. Vieira
The Hall effect has been studied in a series of AuFe samples in the re-entrant concentration range, as well as in the spin glass range. The data demonstrate that the degree of canting of the local spins strongly modifies the anomalous Hall effect, in agreement with theoretical predictions associating canting, chirality and a real space Berry phase. The canon
Sudeshna Chattopadhyay, Alokmay Datta
Atactic polystyrene of two different molecular weights (560900 g.mol-1 and 212400 g.mol-1) have been studied as spin-coated films of thickness varying from ~30 nm to ~250 nm, i.e., ~2Rg to ~12Rg where Rg is the unperturbed radius of gyration of polystyrene, using x-ray reflectivity and transmission UV-spectroscopy. Electron density profiles along depth of th
Xin-Zhong Yan
The density of states modulation recently observed by the scanning tunneling microscopic experiment in the pseudogap state of high-$T_c$ superconductors is explained by the pairing assisted particle transitions under perturbation of a periodic pairing interaction. In such a transition process, a particle with momentum ${\bf k}$ firstly picks up another parti
Navinder Singh Bathinda, N. Kumar
We derive the steady-state electron distribution function for a semiconductor driven far from equilibrium by the inter-band photoexcitation assumed homogeneous over the nanoscale sample. Our analytical treatment is based on the generalization of a stochastic model known for a driven dissipative granular gas. The generalization is physically realizable in a s
Z. Jiang, V. Chandrasekhar
Using a local thermometry technique, we have been able to quantitatively measure the thermal resistance $R^T$ of diffusive Andreev interferometers. We find that $R^T$ is strongly enhanced from its normal state value at low temperatures, and behaves non-linearly as a function of the thermal current through the sample. We also find that the $R^T$ oscillates as
Z. F. Ezawa, M. Eliashvili, G. Tsitsishvili
We investigate the ground-state structure of the bilayer quantum Hall system at the filling factor $ν=2$. Making an exact analysis of the ground state in the SU(4)-invariant limit, we include all other interactions as small perturbation. We carry out analytic calculations and construct phase diagrams for nonzero values of the Zeeman, tunneling and bias inter
Matt Mackie, Jyrki Piilo
We theoretically examine a system of Fermi degenerate atoms coupled to bosonic molecules by a Feshbach resonance, focusing on the superfluid transition to a molecular Bose-Einstein condensate dressed by Cooper pairs of atoms. This problem raises an interest because it is unclear at present whether bimodal density distributions observed recently in 40-K and 6
Imprinting the memory into paste and its visualization as crack patterns in drying process
cond-mat.softAkio Nakahara, Yousuke Matsuo
In the drying process of paste, we can imprint into the paste the order how it should be broken in the future. That is, if we vibrate the paste before it is dried, it remembers the direction of the initial external vibration, and the morphology of resultant crack patterns is determined solely by the memory of the direction. The morphological phase diagram of
Gabriel G. Carlo, Giuliano Benenti, Giulio Casati, Dima L. Shepelyansky
Using the method of quantum trajectories we study a quantum chaotic dissipative ratchet appearing for particles in a pulsed asymmetric potential in the presence of a dissipative environment. The system is characterized by directed transport emerging from a quantum strange attractor. This model exhibits, in the limit of small effective Planck constant, a tran
Broad versus narrow Fano-Feshbach resonances in the BCS-BEC crossover with trapped Fermi atom
cond-mat.supr-conS. Simonucci, P. Pieri, G. C. Strinati
With reference to the broad and narrow Fano-Feshbach resonances of 6Li at about 822 G and 543 G, we show that for the broad resonance a molecular coupled-channel calculation can be mapped with excellent accuracy onto an effective single-channel problem with a contact interaction. This occurs for a wide enough range of the magnetic field, that the full BCS-BE
M. Rosvall, A. Trusina, P. Minnhagen, K. Sneppen
Traffic is constrained by the information involved in locating the receiver and the physical distance between sender and receiver. We here focus on the former, and investigate traffic in the perspective of information handling. We re-plot the road map of cities in terms of the information needed to locate specific addresses and create information city networ
Emil J. Bergholtz, Anders Karlhede
We solve a model that describes an interacting electron gas in the half-filled lowest Landau level on a thin torus, with radius of the order of the magnetic length. The low energy sector consists of non-interacting, one-dimensional, neutral fermions. The ground state, which is homogeneous, is the Fermi sea obtained by filling the negative energy states and t
L. I. Deych
The paper has been withdrawn.
Scaling and Commonality in Anomalous Fluctuation Statistics in Models for Turbulence and Ferromagnetism
cond-mat.stat-mechS. C. Chapman, G. Rowlands, N. W. Watkins
Recently, Portelli et al (2003) have semi-numerically obtained a functional form of the probability distribution of fluctuations in the total energy flow in a model for fluid turbulence. This follows earlier work suggesting that fluctuations in the total magnetization in the 2D X-Y model for a ferromagnet also follow this distribution. Here, starting from th
Daniel Kasen, Tomasz Plewa
We consider some of the spectral and polarimetric signatures of the gravitational confined detonation scenario for Type Ia supernova explosions. In this model, material produced by an off-center deflagration (which itself fails to produce the explosion) forms a metal-rich atmosphere above the white dwarf surface. Using hydrodynamical simulations, we show tha
Daniel A. Dale, Kartik Sheth, George Helou, Michael W. Regan
New and archival interferometric 12CO(1->0) datasets from six nearby galaxies are combined with H_2 2.122um and H-alpha maps to explore in detail the interstellar medium in different star-forming galaxies. We investigate the relation between warm (H_2 at T~2000 K) and cold (CO at T~50 K) molecular gas from 100 pc to 2 kpc scales. On these scales, the ratio o
Catalog of Galaxy Morphology in Four Rich Clusters: Luminosity Evolution of Disk Galaxies at 0.33<z<0.83
astro-phAmelie Saintonge, David Schade, Erica Ellingson, Howard K. C. Yee
Hubble Space Telescope (HST) imaging of four rich, X-ray luminous, galaxy clusters (0.33<z<0.83) is used to produce quantitative morphological measurements for galaxies in their fields. Catalogs of these measurements are presented for 1642 galaxies brighter than F814W(AB)=23.0 . Galaxy luminosity profiles are fitted with three models: exponential disk, de Va
Ilana Klamer, Ron Ekers, Elaine Sadler, Axel Weiss
Using the Australia Telescope Compact Array we have detected CO(1-0) and CO(5-4) from TNJ0924-2201 at z=5.2, the most distant radio galaxy known to date. This is the second highest redshift detection of CO published so far. The CO(1-0) is 250-400 km/sec wide with a peak flux density of 520 +- 115 microJy/beam whilst the CO(5-4) line emission is 200-300 km/se
L. Cambresy, T. H. Jarrett, C. A. Beichman
We present an analysis of the dust optical properties at large scale, for the whole galactic anticenter hemisphere. We used the 2MASS Extended Source Catalog to obtain the total reddening on each galaxy line of sight and we compared this value to the IRAS 100 microns surface brightness converted to extinction by Schlegel et al (1998). We performed a careful
Dirk Pandel, France A. Cordova
The polars VV Pup and V393 Pav were observed with XMM-Newton during states of low accretion rate with peak X-ray luminosities of ~1 x 10^30 and ~1 x 10^31 erg/s, respectively. In both polars, accretion onto the white dwarf was extremely irregular, and the accretion rate varied by more than 1 order of magnitude on timescales of ~1 hr. Our observations suggest
A. von der Linden, T. Erben, P. Schneider, F. J. Castander
Weak lensing surveys provide the possibility of identifying dark matter halos based on their total matter content rather than just the luminous matter content. On the basis of two sets of observations carried out with the CFHT, Erben et al. (2000) presented the first candidate dark clump, i.e. a dark matter concentration identified by its significant weak le
O. Manuel, B. W. Ninham, S. E. Friberg
Efforts to understand unusual weather or abrupt changes in climate have been plagued by deficiencies of the standard solar model (SSM). While it assumes that our primary source of energy began as a homogeneous ball of hydrogen (H) with a steady, well-behaved H-fusion reactor at its core, observations instead reveal a very heterogeneous, dynamic Sun. As examp
Search for Double Transit Extrasolar Planetary Systems: Another Transiting Planet Around OGLE-TR-111 or a False Positive Detection?
astro-phDante Minniti
The search for double transit planetary systems opens new possibilities for the transit searches and for studies of orbital stability, stellar irradiation, and migration scenarios, among others. We explore the OGLE lightcurves of stars with confirmed planetary companions (OGLE-TR-10, OGLE-TR-56, OGLE-TR-111, OGLE-TR-113, and OGLE-TR-132), searching for addit
D. Harbeck, J. Gallagher, E. K. Grebel, A. Koch
We present WIYN observations of the recently discovered And IX dwarf spheroidal (dSph) satellite galaxy of M 31. Our data, obtained at a natural seeing of 0.5'' and just reaching the horizontal branch level, confirm And IX as a dSph galaxy with a distance similar to M 31. A survey for carbon stars shows no evidence for an intermediate-age (1--10 Gyr)
Michael Doran, Joerg Jaeckel
We show that collider experiments have the potential to exclude a light scalar field as well as generic models of modified gravity as dark energy candidates. Our mechanism uses the spectrum radiated by black holes and can equally well be applied to determine the number of light degrees of freedom. We obtain the grey body factors for massive scalar particles
W. A. Dziembowski, T. T. Mizerski
A significant fraction of RR Lyrae stars exhibits amplitude and/or phase modulation known as the the Blazhko effect. The oscillation spectra suggest that, at least in most of the cases, excitation of nonradial modes in addition to the dominant radial modes is responsible for the effect. Though model calculations predict that nonradial modes may be excited, t
N. N. Jetha, I. Sakelliou, M. J. Hardcastle, T. J. Ponman
We present Chandra and VLA observations of two galaxy clusters, Abell 160 and Abell 2462, whose brightest cluster galaxies (BCGs) host wide angle tailed radio galaxies (WATs). We search for evidence of interactions between the radio emission and the hot, X-ray emitting gas, and test various jet termination models. We find that both clusters have cool BCGs at