October 2008 arXiv papers — page 33
Showing 3,201–3,300 of 5,765 papers
Coulomb repulsion and correlation strength in LaFeAsO from Density Functional and Dynamical Mean-Field Theories
cond-mat.str-elV. I. Anisimov, Dm. M. Korotin, M. A. Korotin, A. V. Kozhevnikov
LDA+DMFT (Local Density Approximation combined with Dynamical Mean-Field Theory) computation scheme has been used to calculate spectral properties of LaFeAsO -- the parent compound for new high-T$_c$ iron oxypnictides. Coulomb repulsion $U$ and Hund's exchange $J$ parameters for iron 3d electrons were calculated using \textit {first principles} constrain
J. Dalseno
We present measurements of time-dependent CP violation parameters in B0 --> K0 PI0, B0 --> Ks Pi+ Pi- and B0 --> Ks K+ K- decays. The latter two are extracted using time-dependent Dalitz plot analyses. These results are obtained from a large data sample that contains 657 x 10^6 BBbar pairs collected at the Upsilon(4S) resonance with the Belle detector at the
I. Gazuz, A. M. Puertas, Th. Voigtmann, M. Fuchs
We present a first-principles theory for the active nonlinear microrheology of colloidal model systems: for constant external force on a spherical probe particle embedded in a dense host dispersion, neglecting hydrodynamic interactions, we derive an exact expression for the friction. Within mode-coupling theory (MCT), we discuss the threshold external force
A conformally invariant generalization of string theory to higher-dimensional objects. Hierarchy of coupling constants
gr-qcF. Zaripov
We suggest a conformally invariant generalization of string theory to higher-dimensional objects. As such a model, we consider a conformally invariant $σ$ model. For this theory, the Hamiltonian formalism is constructed, and the full set of constraints is found. The equations obtained are studied under a fixed gauge. It is shown that special cases of the mod
G. Hlawacek, Q. Shen, C. Teichert, A. Lex
Precise control of surface properties including electrical characteristics, wettability, and friction is a prerequisite for manufacturing modern organic electronic devices. The successful combination of bottom up approaches for aligning and orienting the molecules and top down techniques to structure the substrate on the nano and micrometer scale allows the
Nicole P. H. Nesvadba, Matt D. Lehnert
To accommodate the seemingly "anti-hierarchical" properties of galaxies near the upper end of the mass function within our hierarchical paradigm, current models of galaxy evolution postulate a phase of vigorous AGN feedback at high redshift, which effectively terminates star formation by quenching the supply of cold gas. Using the SINFONI IFU on the
Lars Kyllingstad
We study the thermodynamics of massless phi-fourth theory using screened perturbation theory, which is a way to systematically reorganise the perturbative series. The free energy and pressure are calculated through four loops in a double expansion in powers of g^2 and m/T, where m is a thermal mass of order gT. The result is truncated at order g^7. We find t
Pietro Santorelli
We study the effects of final state interactions on the eta(b) => J/psi J/psi decay. In particular, we discuss the effects of the annihilation of eta(b) into two charmed meson and their rescattering into J/psi J/psi. We find that the inclusion of this contribution may enhance the short-distance branching ratio up to about 2 orders of magnitude.
J. Miao, G. J. White, M. A. Thompson, R. P. Nelson
A new Radiative Driven Implosion (RDI) model based on Smoothed Particle Hydrodynamics (SPH) technique is developed and applied to investigate the morphological evolutions of molecular clouds under the effect of ionising radiation. This model self-consistently includes the self-gravity of the cloud in the hydrodynamical evolution, the UV radiation component i
Magdalena Stobińska, G. J. Milburn, Krzysztof Wódkiewicz
According to the Gottesmann-Knill theorem the non-Gaussian states are necessary component for a nontrivial quantum computation. We show two efficient and deterministic methods of $χ^{(3)}$ non-Gaussian state generation for a cavity mode using a single trapped ion. Both require ion motional state transfer to the cavity field. The methods are experimentally fe
From protein binding to pharmacokinetics: a novel approach to active drug absorption prediction
q-bio.QMP. O. Fedichev, T. V. Kolesnikova, A. A. Vinnik
Due to inherent complexity active transport presents a landmark hurdle for oral absorption properties prediction. We present a novel approach carrier-mediated drug absorption parameters calculation based on entirely different paradigm than QSPR. We capitalize on recently emerged ideas that molecule activities against a large protein set can be used for predi
Cell size distribution in a random tessellation of space governed by the Kolmogorov-Johnson-Mehl-Avrami model: Grain size distribution in crystallization
cond-mat.mtrl-sciJordi Farjas, Pere Roura
The space subdivision in cells resulting from a process of random nucleation and growth is a subject of interest in many scientific fields. In this paper, we deduce the expected value and variance of these distributions while assuming that the space subdivision process is in accordance with the premises of the Kolmogorov-Johnson-Mehl-Avrami model. We have no
M. Manninen, S. M. Reimann
This short review presents a few case studies of finite electron systems for which strong correlations play a dominant role. In simple metal clusters, the valence electrons determine stability and shape of the clusters. The ionic skeleton of alkali metals is soft, and cluster geometries are often solely determined by electron correlations. In quantum dots an
Leonel Gutierrez, Antti Tamm, John Beckman, Louis Abramson
Several recent studies indicate that bulges are more complex than merely structureless relaxed stellar systems. We study the HST images of a sample of 130 nearby early type (S0-Sab) disc galaxies and detect pure structureless bulges with the Sersic index n > 2 for only 12% of the galaxies. Other galaxies show varied substructure in their inner regions (inner
Electronic band structures and intra-atomic interactions in layered quaternary oxyarsenides LaZnAsO and YZnAsO
cond-mat.mtrl-sciV. V. Bannikov, I. R. Shein, A. L. Ivanovskii
First-principle FLAPW-GGA band structure calculations are employed to obtain the structural, electronic properties and chemical bonding picture for two related layered phases, namely, quaternary oxyarsenides LaZnAsO and YZnAsO. These compounds are found to be direct-transition type semiconductors with the GGA gaps of about 0.65-1.30 eV. The peculiarities of
Jing Xia, V. Shelukhin, M. Karpovski, A. Kapitulnik
Measurements of the polar Kerr effect using a zero-area-loop Sagnac magnetometer on Pb/Ni and Al/(Co-Pd) proximity-effect bilayers show unambiguous evidence for the "inverse proximity effect," in which the ferromagnet (F) induces a finite magnetization in the superconducting (S) layer. To avoid probing the magnetic effects in the ferromagnet, the sup
Netanel H. Lindner, Assa Auerbach, Daniel P. Arovas
In two dimensions a vortex lattice can melt by quantum fluctuations into a non-superfluid Quantum Vortex Liquid (QVL). To determine the melting conditions, we compute the bare vortex hopping rate by exact diagonalization of square clusters near half filling. Mapping our effective Hamiltonian to the Boson Coloumb Liquid simulated in Phys. Rev. Lett. 73, 826 (
Matthew O. Jackson
I examine a random network model where nodes are categorized by type and linking probabilities can differ across types. I show that as homophily increases (so that the probability to link to other nodes of the same type increases and the probability of linking to nodes of some other types decreases) the average distance and diameter of the network are unchan
Valerio Faraoni
We review the state of the art of f(R) theories of gravity (in their various formulations), which have been proposed as an explanation of the cosmic acceleration alternative to dark energy. The successes of f(R) gravity are discussed, together with the challenges imposed by minimal criteria for their viability.
N. N. Achasov
Outline: 1. Introduction, 2. Confinement, chiral dynamics and light scalar mesons, 3. Chiral shielding of σ(600), chiral constraints, σ(600), f_0(980) and their mixing in ππ\toππ, ππ\to K\bar K, and ϕ\toγ\pi0\pi0, 4. The ϕmeson radiative decays on light scalar resonances. 5. Why a0(980) and f0(980) are not the K\bar K molecules. 6. Light scalars in γγcollisi
K. F. Tan, J. R. Shi, G. Zhao
We have determined beryllium abundances for 25 metal-poor stars based on the high resolution and high signal-to-noise ratio spectra from the VLT/UVES database. Our results confirm that Be abundances increase with Fe, supporting the global enrichment of Be in the Galaxy. Oxygen abundances based on [O I] forbidden line implies a linear relation with a slope cl
Angela K. Speck, Adrian B. Corman, Kristina Wakeman, Caleb H. Wheeler
Infrared carbon stars without visible counterparts are generally known as extreme carbon stars. We have selected a subset of these stars with absorption features in the 10-13 $μ$m range, which has been tentatively attributed to silicon carbide (SiC). We add three new objects meeting these criterion to the seven previously known, bringing our total sample to
Nicholas P. Warner
In string theory, black-hole backgrounds are far from unique and there are large families of completely smooth, horizonless geometries with the same structure as a black hole from infinity down to the neighborhood of the black-hole horizon. These microstate geometries cap off in foam of topological bubbles. I review some of the recent progress in constructin
Ultracold Atoms in 1D Optical Lattices: Mean Field, Quantum Field, Computation, and Soliton Formation
cond-mat.otherR. V. Mishmash, L. D. Carr
In this work, we highlight the correspondence between two descriptions of a system of ultracold bosons in a one-dimensional optical lattice potential: (1) the discrete nonlinear Schrödinger equation, a discrete mean-field theory, and (2) the Bose-Hubbard Hamiltonian, a discrete quantum-field theory. The former is recovered from the latter in the limit of a p
C. Henning, H. Kählert, P. Ludwig, A. Melzer
A combined theoretical and experimental analysis of the normal modes of three-dimensional spherially confined Yukawa clusters is presented. Particular attention is paid to the breathing mode and the existence of multiple monopole oscillations in Yukawa systems. Finally, the influence of dissipation on the mode spectrum is investigated.
Peter Adshead, Richard Easther
We review the free parameters in the concordance cosmology, and those which might be added to this set as the quality of astrophysical data improves. Most concordance parameters encode information about otherwise unexplored aspects of high energy physics, up to the GUT scale via the "inflationary sector," and possibly even the Planck scale in the cas
Jinho Baik, Robert Buckingham, Jeffery DiFranco, Alexander Its
We evaluate the total integral from negative infinity to positive infinity of all global solutions to the Painleve II equation on the real line. The method is based on the interplay between one of the equations of the associated Lax pair and the corresponding Riemann-Hilbert problem. In addition, we evaluate the total integral of a function related to a spec
Vigleik Angeltveit, Michael Hill, Tyler Lawson
We apply an announced result of Blumberg-Cohen-Schlichtkrull to reprove (under restricted hypotheses) a theorem of Mahowald: the connective real and complex K-theory spectra are not Thom spectra.
Masahiro N. Machida
The formation of a circumplanetary disk and accretion of angular momentum onto a protoplanetary system are investigated using 3D hydrodynamical simulations. The local region around a protoplanet in a protoplanetary disk is considered with sufficient spatial resolution: the region from outside the Hill sphere to the Jovian radius is covered by the nested-grid
Hidden Galilean symmetry, conservation laws and emergence of spin current in the soliton sector of chiral helimagnet
cond-mat.str-elI. G. Bostrem, J. Kishine, R. V. Lavrov, A. S. Ovchinnikov
Motivated by the spin current problem in chiral helimagnet, we rigorously elucidated the hidden Galilean invariance in the chiral XY model under the magnetic field. The Lie group analysis is applied to the differential equations of the continuum theory of the chiral helimagnet with the parity-violating Dzyaloshinskii-Morya coupling under a transversal magnet
The Star Formation Efficiency in Nearby Galaxies: Measuring Where Gas Forms Stars Effectively
astro-phAdam K. Leroy, Fabian Walter, Elias Brinks, Frank Bigiel
We measure the star formation efficiency (SFE), the star formation rate per unit gas, in 23 nearby galaxies and compare it to expectations from proposed star formation laws and thresholds. We use HI maps from THINGS and derive H2 maps from HERACLES and BIMA SONG CO. We estimate the star formation rate by combining GALEX FUV maps and SINGS 24 micron maps, inf
M. Cantiello, N. Langer, I. Brott, A. de Koter
We present results from the first extensive study of convection zones in the envelopes of hot massive stars, which are caused by opacity peaks associated with iron and helium ionization. These convective regions can be located very close to the stellar surface. Recent observations of microturbulence in massive stars from the VLT-Flames survey are in good agr
Peter Morgan
The violation of Bell inequalities by experiment has convinced physicists that we cannot maintain a classical view of the world. When we argue against the possibility of local realist hidden-variable models, however, the ubiquitous requirement of realism, that "measurement results depend on pre-existing properties of objects that are independent of the m
Alexandru Nica
Let k be a positive integer and let D_k denote the space of joint distributions for k-tuples of selfadjoint elements in C*-probability space. The paper studies the concept of "subordination distribution of μ\boxplus νwith respect to ν" for μ, ν\in D_k, where \boxplus is the operation of free additive convolution on D_k. The main tools used in this st
Gene Abrams, Mark Tomforde
For any countable graph $E$, we investigate the relationship between the Leavitt path algebra $L_{\C}(E)$ and the graph C*-algebra $C^*(E)$. For graphs $E$ and $F$, we examine ring homomorphisms, ring *-homomorphisms, algebra homomorphisms, and algebra *-homomorphisms between $L_{\C}(E)$ and $L_{\C}(F)$. We prove that in certain situations isomorphisms betwe
LCDM predictions for galaxy protoclusters I: the relation between galaxies, protoclusters and quasars at z~6
astro-phRoderik Overzier, Qi Guo, Guinevere Kauffmann, Gabriella De Lucia
Motivated by recent observational studies of the environment of z~6 QSOs, we have used the Millennium Run (MR) simulations to construct a very large (~20 deg^2) mock redshift survey of star-forming galaxies at z~6. We use this simulated survey to study the relation between density enhancements in the distribution of i-dropouts and Lya-emitters, and their rel
Entanglement under the renormalization-group transformations on quantum states and in quantum phase transitions
quant-phTzu-Chieh Wei
We consider quantum states under the renormalization-group (RG) transformations introduced by Verstraete et al. [Phys. Rev. Lett. 94, 140601 (2005)] and propose a quantification of entanglement under such RG (via the geometric measure of entanglement). We examine the resulting entanglement under RG for the ground states of "matrix-product-state" (MPS
G. A. Shields, E. W. Bonning, S. Salviander
SDSS J092712.65+294344.0 has been proposed as a candidate for a supermassive black hole (~10^8.8 solar masses) ejected at high speed from the host galactic nucleus by gravitational radiation recoil, or alternatively for a supermassive black hole binary. This is based on a blueshift of 2650 km/s of the broad emission lines ("b-system") relative to the
Andrew Raich
The purpose of this article is to study compactness of the complex Green operator on CR manifolds of hypersurface type. We introduce (CR-P_q), a potential theoretic condition on $(0,q)$-forms that generalizes Catlin's property (P_q) to CR manifolds of arbitrary codimension. We prove that if an embedded CR-manifold of hypersurface type satisfies (CR-P_q)
Bruno Henriques, Peter Thomas, Seb Oliver, Isaac Roseboom
[abridged] We present a statistical exploration of the parameter space of the De Lucia and Blaizot version of the Munich semi-analytic model built upon the millennium dark matter simulation. This is achieved by applying a Monte Carlo Markov Chain method to constrain the 6 free parameters that define the stellar and black-hole mass functions at redshift zero.
I. Pascucci, D. Apai, K. Luhman, Th. Henning
We present the first comprehensive, comparative Spitzer/IRS study of the dust and gas properties of disks around young sun-like stars (K1-M5) and cool stars/brown dwarfs (M5-M9). The comparison of these two large samples of over 60 sources reveal major differences in the evolution of both the dust and gas components.We report the first detections of organic
V. Kashcheyevs, C. Karrasch, T. Hecht, A. Weichselbaum
Understanding the charging of exceptionally narrow levels in quantum dots in the presence of interactions remains a challenge within mesoscopic physics. We address this fundamental question in the generic model of a narrow level capacitively coupled to a broad one. Using bosonization we show that for arbitrary capacitive coupling charging can be described by
Neutron-Rich Freeze-Out in Viscously Spreading Accretion Disks Formed from Compact Object Mergers
astro-phB. D. Metzger, A. L. Piro, E. Quataert
Accretion disks with masses ~0.001-0.1 Msun form during the merger of neutron star (NS)-NS and black hole-NS binaries. Initially, such hyper-accreting disks cool efficiently by neutrino emission and their composition is driven neutron-rich by pair captures under degenerate conditions. However, as the disk viscously spreads and its temperature drops, cooling
L. García, L. E. González, M. Lomnitz, C. Villarreal
This manuscript has been withdrawn, since the authors have detected numerical inaccuracies that invalidate their main results concerning the existence of repulsive Casimir forces within a rectangular piston. Formulas presented in the manuscript keep still valid. The authors deeply apologize for this mistake.
Xiyu Zhu, Fei Han, Peng Cheng, Gang Mu
Since the discovery of superconductivity\cite{1} at 26 K in oxy-pnictide $LaFeAsO_{1-x}F_x$, enormous interests have been stimulated in the fields of condensed matter physics and material sciences. Among the five different structures in this broad type of superconductors\cite{2,3,4,5,6}, the ZrCuSiAs structure has received special attention since the $T_c$ h
Two approaches for the gravitational self force in black hole spacetime: Comparison of numerical results
gr-qcNorichika Sago, Leor Barack, Steven Detweiler
Recently, two independent calculations have been presented of finite-mass ("self-force") effects on the orbit of a point mass around a Schwarzschild black hole. While both computations are based on the standard mode-sum method, they differ in several technical aspects, which makes comparison between their results difficult--but also interesting. Bara
Martin Ammon, Johanna Erdmenger, Matthias Kaminski, Patrick Kerner
We consider thermal strongly-coupled N=2 SYM theory with fundamental matter at finite isospin chemical potential. Using gauge/gravity duality, i.e. a probe of two flavor D7-branes embedded in the AdS black hole background, we find a critical temperature at which the system undergoes a second order phase transition. The critical exponent of this transition is
L. Chen, I. Chiorescu
A characteristic of spin reversal in the presence of phonon-bottleneck is the deviation of the magnetization cycle from a reversible function into an opened hysterezis cycle. In recent experiments on molecular magnets (e.g. V$_{15}$ and Ru$_2$), the zero-field level repulsion was sufficiently large to ensure an otherwise adiabatic passage through zero-field
Soyoung Moon
We prove that the amalgamated free product of two free groups of rank two over a common cyclic subgroup, admits an amenable, faithful, transitive action on an infinite countable set. We also show that any finite index subgroup admits such an action, which applies for example to surface groups and fundamental groups of surface bundles over $\mathbb{S}^1$.
M. E. Convery
We report new results from CDF on single-diffractive dijet and W/Z production, and on exclusive dijet, diphoton, and dilepton production in proton-antiproton collisions at sqrt{s}=1.96 TeV at the Fermilab Tevatron. The measured exclusive dijet and diphoton cross sections provide a test of theoretical predictions for exclusive Higgs production at the LHC.
M. Polletta, A. Omont, S. Berta, J. Bergeron
We report the discovery of two sources at z=3.867 and z=3.427 that exhibit powerful starburst and AGN activities. They benefit from data from radio to X rays from the CFHTLS-D1/SWIRE/XMDS surveys. Follow-up optical and near-infrared spectroscopy, and millimeter IRAM/MAMBO observations are also available. We performed an analysis of their spectral energy dist
Florina Halasan
We prove persistence of absolutely continuous spectrum for the Anderson model on a general class of tree-like graphs.
Anand D. Sarwate, Alexandros G. Dimakis
The influence of node mobility on the convergence time of averaging gossip algorithms in networks is studied. It is shown that a small number of fully mobile nodes can yield a significant decrease in convergence time. A method is developed for deriving lower bounds on the convergence time by merging nodes according to their mobility pattern. This method is u
Thermocapillary effects in driven dewetting and self-assembly of pulsed laser-irradiated metallic films
physics.flu-dynA. Atena, M. Khenner
In this paper the lubrication-type dynamical model is developed of a molten, pulsed laser-irradiated metallic film. The heat transfer problem that incorporates the absorbed heat from a single beam or interfering beams is solved analytically. Using this temperature field, we derive the 3D long-wave evolution PDE for the film height. To get insights into dynam
Comparison of structure and transport properties of concentrated hard and soft sphere fluids
cond-mat.softErik Lange, Jose B. Caballero, Antonio M. Puertas, Matthias Fuchs
Using Newtonian and Brownian dynamics simulations, the structural and transport properties of hard and soft spheres have been studied. The soft spheres were modeled using inverse power potentials ($V\sim r^{-n}$, with $1/n$ the potential softness). Although the pressure, diffusion coefficient and viscosity depend at constant density on the particle softness
Pavel Frantsuzov, Masaru Kuno, Boldizsar Janko, Rudolph A. Marcus
Virtually all known fluorophores, including semiconductor nanoparticles, nanorods and nanowires exhibit unexplainable episodes of intermittent emission blinking. A most remarkable feature of the fluorescence intermittency is a universal power law distribution of on- and off-times. For nanoparticles the resulting power law extends over an extraordinarily wide
Rui Gonçalves, Alberto Pinto
We analyze the constituents stocks of the Dow Jones Industrial Average (DJIA30) and the Standard & Poor's 100 index (S&P100) of the NYSE stock exchange market. Surprisingly, we discover the data collapse of the histograms of the DJIA30 price fluctuations and of the S&P100 price fluctuations to the universal non-parametric Bramwell-Holdsworth-Pinton (BHP)
Markus Tiersch, Fernando de Melo, Andreas Buchleitner
We show that the entanglement evolution of an open quantum system is the same for the vast majority of initial pure states, in the limit of large Hilbert space dimensions.
P. J. Käpylä, A. Brandenburg
Dynamo action owing to helically forced turbulence and large-scale shear is studied using direct numerical simulations. The resulting magnetic field displays propagating wave-like behavior. This behavior can be modelled in terms of an αΩdynamo. In most cases super-equipartition fields are generated. By varying the fraction of helicity of the turbulence the r
Tatiana Shulman
Let $p$ be a polynomial in one variable whose roots either all have multiplicity more than 1 or all have multiplicity exactly 1. It is shown that the universal $C^*$-algebra of a relation $p(x)=0$, $\|x\| \le 1$ is semiprojective. In the case of all roots multiple it is shown that the universal $C^*$-algebra is also residually finite-dimensional. Application
Hajo Leschke, Rainer Ruder
In a reasonably self-contained and explicit presentation we illustrate the efficiency of the Feynman-Kac formula for the rigorous derivation of three inequalities of interest in non-relativistic quantum mechanics.
HINODE Observations of Chromospheric Brightenings in the Ca II H Line during small-scale Flux Emergence Events
astro-phS. L. Guglielmino, F. Zuccarello, P. Romano, L. R. Bellot Rubio
\ion{Ca}{2} H emission is a well-known indicator of magnetic activity in the Sun and other stars. It is also viewed as an important signature of chromospheric heating. However, the \ion{Ca}{2} H line has not been used as a diagnostic of magnetic flux emergence from the solar interior. Here we report on Hinode observations of chromospheric \ion{Ca}{2} H brigh
Michael Murphy, Liang Jiang, Navin Khaneja, Tommaso Calarco
Effective transport of quantum information is an essential element of quantum computation. We consider the problem of transporting a quantum state by using a moving potential well, while maintaining the encoded quantum information. In particular, we look at a set of cases where the input control defining the position of the potential well is subject to diffe
Tyler J. Jarvis, Takashi Kimura
We provide a formula describing the G-module structure of the Hurwitz-Hodge bundle for admissible G-covers in terms of the Hodge bundle of the base curve, and more generally, for describing the G-module structure of the push-forward to the base of any sheaf on a family of admissible G-covers. This formula can be interpreted as a representation-ring-valued re
J. Haglund, K. Luoto, S. Mason, S. van Willigenburg
We introduce a new basis for quasisymmetric functions, which arise from a specialization of nonsymmetric Macdonald polynomials to standard bases, also known as Demazure atoms. Our new basis is called the basis of quasisymmetric Schur functions, since the basis elements refine Schur functions in a natural way. We derive expansions for quasisymmetric Schur fun
Dynamics in the Metabasin Space of a Lennard-Jones Glass Former: Connectivity and Transition Rates
cond-mat.softYasheng Yang, Bulbul Chakraborty
Using simulations, we construct the effective dynamics in metabasin space for a Lennard-Jones glass-former. Metabasins are identified via a scheme that measures transition rates between inherent structures, and generates clusters of inherent structures by drawing in branches that have the largest transition rates. The effective dynamics is shown to be Markov
Energetic selection of ordered states in a model of the Er2Ti2O7 frustrated pyrochlore XY antiferromagnet
cond-mat.stat-mechP. A. McClarty, S. H. Curnoe, M. J. P. Gingras
We consider the possibility that the discrete long-range ordered states of Er2Ti2O7 are selected energetically at the mean field level as an alternative scenario that suggests selection via thermal fluctuations. We show that nearest neighbour exchange interactions alone are not sufficient for this purpose, but that anisotropies arising from excited single io
Fei Han, Xiyu Zhu, Gang Mu, Peng Cheng
We have successfully synthesized the fluo-arsenide SrFeAsF, a new parent phase with the ZrCuAsSi structure. The temperature dependence of resistivity and dc magnetization both reveal an anomaly at about T_{an} = 173 K, which may correspond to the structural and/or Spin-Density-Wave (SDW) transition. Strong Hall effect and magnetoresistance were observed belo
E. Corrigan
Invited contribution to the collection of articles: `The Birth of String Theory', edited by Andrea Cappelli, Elena Castellani, Filippo Colomo and Paolo Di Vecchia.
Mohammad Moghaddam
We prove that the sequence of MacLane key polynomials constructed in \cite{Mac1} and \cite{Sp2} for a valuation extension $(K,ν)\subset (K(x),μ)$ is finite, provided that both $ν$ and $μ$ are divisorial and $μ$ is centered over an analytically irreducible local domain $(R,\frak{m})\subset K[x]$. As a corollary, we prove Izumi's theorem on comparison of d
A. B. Kuzmenko, E. van Heumen, D. van der Marel, P. Lerch
We present infrared spectra (0.1-1 eV) of electrostatically gated bilayer graphene as a function of doping and compare it with tight binding calculations. All major spectral features corresponding to the expected interband transitions are identified in the spectra: a strong peak due to transitions between parallel split-off bands and two onset-like features
Michael I Buchoff, Jiunn-Wei Chen, Andre Walker-Loud
In this report we describe both I=2 and I=0 pi-pi scattering for twisted mass lattice QCD utilizing twisted mass chiral perturbation theory at next-to-leading order. Focusing on the lattice spacing (b) corrections, we demonstrate that in the exotic I=2, I_3=+-2 channels, the leading scaling violations of pi-pi scattering at maximal twist begin at O(m_pi^2 b^
Ashley Montanaro, Tobias J. Osborne
In this paper we introduce the study of quantum boolean functions, which are unitary operators f whose square is the identity: f^2 = I. We describe several generalisations of well-known results in the theory of boolean functions, including quantum property testing; a quantum version of the Goldreich-Levin algorithm for finding the large Fourier coefficients
D. Darau, G. Begemann, A. Donarini, M. Grifoni
Interference effects strongly affect the transport characteristics of a benzene single-electron transistor (SET) and for this reason we call it interference SET (I-SET). We focus on the effects of degeneracies between many-body states of the isolated benzene. We show that the particular current blocking and selective conductance suppression occurring in the
Martin Gonzalez-Alonso, Antonio Pich, Joaquim Prades
Using recent precise hadronic tau-decay data on the V-A spectral function and general properties of QCD such as analyticity, the operator product expansion and chiral perturbation theory, we get accurate values for the QCD chiral order parameters L_10 and C_87. At order p^4 we obtain L_10^r(M_rho)=-(5.22+-0.06)10^-3, whereas at order p^6 we get L_10^r(M_rho)
A. S. Meshkov, E. F. Ostretsov, W. V. Pogosov, I. A. Ryzhikov
We study experimentally the photoconductivity of CdS-CdSe sintered granular films obtained by the screen printing method. We mostly focus on the dependences of photoconductivity on film's microstructure, which varies with changing heat-treatment conditions. The maximum photoconductivity is found for samples with compact packing of individual grains, whic
Mark Dukes, Astrid Reifegerste
In this paper we study a mapping from permutations to Dyck paths. A Dyck path gives rise to a (Young) diagram and we give relationships between statistics on permutations and statistics on their corresponding diagrams. The distribution of the size of this diagram is discussed and a generalisation given of a parity result due to Simion and Schmidt. We propose
Z. Kim, V. Zaretskey, Y. Yoon, J. F. Schneiderman
We have observed a few distinct anomalous avoided level crossings and voltage dependent transitions in the excited state spectrum of an Al/AlOx/Al Cooper-pair box (CPB). The device was measured at 40 mK in the 15 - 50 GHz frequency range. We find that a given level crosses the CPB spectrum at two different gate voltages; the frequency and splitting size of t
Olivier Durieu, Dalibor Volny
We show by a constructive proof that in all aperiodic dynamical system, for all sequences $(a_n)_{n\in\N}\subset\R_+$ such that $a_n\nearrow\infty$ and $\frac{a_n}{n}\to 0$ as $n\to\infty$, there exists a set $A\in\A$ having the property that the sequence of the distributions of $(\frac{1}{a_{n}}S_{n}(\ind_A-μ(A)))_{n\in\N}$ is dense in the space of all prob
S. Abraham, P. Fernandez de Cordoba, J. M. Isidro, J. L. G. Santander
We construct the classical mechanics associated with a conformally flat Riemannian metric on a compact, n-dimensional manifold without boundary. The corresponding gradient Ricci flow equation turns out to equal the time-dependent Hamilton-Jacobi equation of the mechanics so defined.
Abdelhak Djouadi
One of the main motivations for low energy supersymmetric theories is their ability to address the hierarchy and naturalness problems in the Higgs sector of the Standard Model. In these theories, at least two doublets of scalar fields are required to break the electroweak symmetry and to generate the masses of the elementary particles, resulting in a rather
O. N. Hartmann
The production of mesons containing strangeness is studied using elementary and heavy-ion probes with the FOPI detector at GSI-SIS. The observed inclusive cross section of neutral kaons points to an in-medium modification in the production. The momentum dependent ratio of cross sections of light and heavy target nuclei turns out to be a sensitive observable
Momentum-resolved single-particle spectral function for TiOCl from a combination of density functional and variational cluster calculations
cond-mat.str-elM. Aichhorn, T. Saha-Dasgupta, R. Valenti, S. Glawion
We present results for the momentum-resolved single-particle spectral function of the low-dimensional system TiOCl in the insulating state, obtained by a combination of ab initio Density Functional Theory (DFT) and Variational Cluster (VCA) calculations. This approach allows to combine a realistic band structure and a thorough treatment of the strong correla
Resolving long-range spatial correlations in jammed colloidal systems using photon correlation imaging
cond-mat.softAgnes Duri, David A. Sessoms, Veronique Trappe, Luca Cipelletti
We introduce a new dynamic light scattering method, termed photon correlation imaging, which enables us to resolve the dynamics of soft matter in space and time. We demonstrate photon correlation imaging by investigating the slow dynamics of a quasi two-dimensional coarsening foam made of highly packed, deformable bubbles and a rigid gel network formed by di
Manuel Manas, Luis Martinez Alonso
The factorization problem of the multi-component 2D Toda hierarchy is used to analyze the dispersionless limit of this hierarchy. A dispersive version of the Whitham hierarchy defined in terms of scalar Lax and Orlov--Schulman operators is introduced and the corresponding additional symmetries and string equations are discussed. Then, it is shown how KP and
Changhyun Ahn
We consider one of the well-known solutions in eleven-dimensional supergravity where the seven-dimensional Einstein space is given by a SO(3)-bundle over the CP^2. By reexaming the AdS_4 supergravity scalar potential, the holographic renormalization group flow from N=(0,1) SU(3) x SU(2)-invariant UV fixed point to N=(3,0) SU(3) x SU(2)-invariant IR fixed poi
Eleonora Nagali, Fabio Sciarrino, Francesco De Martini, Lorenzo Marrucci
The optical "spin-orbit" coupling occurring in a suitably patterned nonuniform birefringent plate known as `q-plate' allows entangling the polarization of a single photon with its orbital angular momentum (OAM). This process, in turn, can be exploited for building a bidirectional "spin-OAM interface", capable of transposing the quantum in
Scanning tunneling microscopy and kinetic Monte Carlo investigation of Cesium superlattices on Ag(111)
cond-mat.mtrl-sciM. Ziegler, J. Kroeger, R. Berndt, A. Filinov
Cesium adsorption structures on Ag(111) were characterized in a low-temperature scanning tunneling microscopy experiment. At low coverages, atomic resolution of individual Cs atoms is occasionally suppressed in regions of an otherwise hexagonally ordered adsorbate film on terraces. Close to step edges Cs atoms appear as elongated protrusions along the step e
G. Aragon-Camarasa, G. Aragon-Gonzalez, J. L. Aragon, M. A. Rodriguez-Andrade
The Clifford algebra of a n-dimensional Euclidean vector space provides a general language comprising vectors, complex numbers, quaternions, Grassman algebra, Pauli and Dirac matrices. In this work, we present an introduction to the main ideas of Clifford algebra, with the main goal to develop a package for Clifford algebra calculations for the computer alge
Dusko Bogdanic
In this paper we construct non-negative gradings on a basic Brauer tree algebra $A_Γ$ corresponding to an arbitrary Brauer tree $Γ$ of type $(m,e)$. We do this by transferring gradings via derived equivalence from a basic Brauer tree algebra $A_S$, whose tree is a star with the exceptional vertex in the middle, to $A_Γ$. The grading on $A_S$ comes from the t
Sebastien Renaux-Petel, Gianmassimo Tasinato
We adopt a covariant formalism to derive exact evolution equations for nonlinear perturbations, in a universe dominated by two scalar fields. These scalar fields are characterized by non-canonical kinetic terms and an arbitrary field space metric, a situation typically encountered in inflationary models inspired by string theory. We decompose the nonlinear s
B. Küng, O. Pfäffli, S. Gustavsson, T. Ihn
We present time-resolved charge sensing measurements on a GaAs double quantum dot with two proximal quantum point contact (QPC) detectors. The QPC currents are analyzed with cross-correlation techniques, which enables us to measure dot charging and discharging rates for significantly smaller signal-to-noise ratios than required for charge detection with a si
V. Schwämmle, Silvio M. D. Queirós, E. Brigatti, T. Tchumatchenko
The current distribution of language size in terms of speaker population is generally described using a lognormal distribution. Analyzing the original real data we show how the double-Pareto lognormal distribution can give an alternative fit that indicates the existence of a power law tail. A simple Monte Carlo model is constructed based on the processes of
John Walsh
Radiative and leptonic decays of B-mesons represent an excellent laboratory for the search for New Physics. I present here recent results on radiative and leptonic decays from the Belle and BABAR collaborations.
Arthur Jabs
The spin-statistics connection is derived in a simple manner under the postulates that the original and the exchange wave functions are simply added, and that the azimuthal phase angle, which defines the orientation of the spin part of each single-particle spin-component eigenfunction in the plane normal to the spin-quantization axis, is exchanged along with
L. V. Bogdanov
A class of multidimensional integrable hierarchies connected with commutation of general (unreduced) (N+1)-dimensional vector fields containing derivative over spectral variable is considered. They are represented in the form of generating equation, as well as in the Lax-Sato form. A dressing scheme based on nonlinear vector Riemann problem is presented for
U. Klein
It is shown that Schroedinger's equation may be derived from three postulates. The first is a kind of statistical metamorphosis of classical mechanics, a set of two relations which are obtained from the canonical equations of particle mechanics by replacing all observables by statistical averages. The second is a local conservation law of probability wit
Joseph Chuang, Andrey Lazarev
We show that an algebra over a cyclic operad supplied with an additional linear algebra datum called Hodge decomposition admits a minimal model whose structure maps are given in terms of summation over trees. This minimal model is unique up to homotopy.
Simone Faro, Thierry Lecroq
The binary string matching problem consists in finding all the occurrences of a pattern in a text where both strings are built on a binary alphabet. This is an interesting problem in computer science, since binary data are omnipresent in telecom and computer network applications. Moreover the problem finds applications also in the field of image processing a
V. Metaftsis, E. Raptis, D. Varsos
We show that an HNN-extension with finitely generated abelian base group is Z-linear if and only if it is residually finite.