June 2004 arXiv papers — page 12

Elias P. Gyftopoulos, Michael R. von Spakovsky

We review both the Einstein, Podolsky, Rosen (EPR) paper about the completeness of quantum theory, and Schrodinger's responses to the EPR paper. We find that both the EPR paper and Schrodinger's responses, including the cat paradox, are not consistent with the current understanding of quantum theory and thermodynamics. Because both the EPR paper and

Noah Linden, Andreas Winter

Strong subadditivity of von Neumann entropy, proved in 1973 by Lieb and Ruskai, is a cornerstone of quantum coding theory. All other known inequalities for entropies of quantum systems may be derived from it. Here we prove a new inequality for the von Neumann entropy which we prove is independent of strong subadditivity: it is an inequality which is true for

Eliano Pessa, Giuseppe Vitiello

We discuss some features of the dissipative quantum model of brain in the frame of the formalism of quantum dissipation. Such a formalism is based on the doubling of the system degrees of freedom. We show that the doubled modes account for the quantum noise in the fluctuating random force in the system-environment coupling. Remarkably, such a noise manifests

Kerim Savran, Tugrul Hakioglu, Emine Mese

We examine the conditions in favor and necessity of a realistic multileveled description of a decohering quantum system. Under these conditions approximate techniques to simplify a multileveled system by its first two levels is unreliable and a realistic multilevel description in the formulation of decoherence is unavoidable. In this regard, our first crucia

Y. Li, T. Shi, B. Chen, Z. Song

We explore the physical mechanism to coherently transfer the quantum information of spin by connecting two spins to an isotropic antiferromagnetic spin ladder system as data bus. Due to a large spin gap existing in such a perfect medium, the effective Hamiltonian of the two connected spins can be archived as that of Heisenberg type, which possesses a ground

S. Albeverio, S. M. Fei, P. Kurasov

Point interactions for the second derivative operator in one dimension are studied. Every operator from this family is described by the boundary conditions which include a $ 2 \times 2 $ real matrix with the unit determinant and a phase. The role of the phase parameter leading to unitary equivalent operators is discussed in the present paper. In particular i

M. Barbieri, F. De Martini, G. Di Nepi, P. Mataloni

We have experimentally tested the non local properties of the states generated by a high brilliance source of entanglement which virtually allows the direct measurement of the full set of photon pairs created by the basic QED process implied by the parametric quantum scattering. Standard Bell measurements and Bell's inequality violation test have been re

Zhanjun Zhang, Zhongxiao Man, Yong Li

The eavesdropping scheme proposed by Wójcik [Phys. Rev. Lett. {\bf 90},157901(2003)] on the quantum communication protocol of Boström and Felbinger [Phys. Rev. Lett. {\bf 89}, 187902(2002)] is improved by constituting a new set of attack operations. The improved scheme only induces half of the eavesdropping losses in Wójcik's scheme, therefore, in a larg

J. R. Torgerson, S. K. Lamoreaux

The frequency spectrum of the finite temperature correction to the Casimir force can be determined by use of the Lifshitz formalism for metallic plates of finite conductivity. We show that the correction for the $TE$ electromagnetic modes is dominated by frequencies so low that the plates cannot be modelled as ideal dielectrics. We also address issues relati

Yu. I. Bogdanov

The root estimator of quantum states based on the expansion of the psi function in terms of system eigenfunctions followed by estimating the expansion coefficients by the maximum likelihood method is considered. In order to provide statistical completeness of the analysis, it is necessary to perform measurements in mutually complementing experiments (accordi

Kevin S. Brown, Colin C. Hill, Guillermo A. Calero, Kelvin H. Lee

It is becoming increasingly appreciated that the signal transduction systems used by eukaryotic cells to achieve a variety of essential responses represent highly complex networks rather than simple linear pathways. While significant effort is being made to experimentally measure the rate constants for individual steps in these signaling networks, many of th

Istvan Albert, Reka Albert

High-throughput protein interaction detection methods are strongly affected by false positive and false negative results. Focused experiments are needed to complement the large-scale methods by validating previously detected interactions but it is often difficult to decide which proteins to probe as interaction partners. Developing reliable computational met

K. E. Kechedzhy O. V. Usatenko, V. A. Yampol'skii

The binary many-step Markov chain with the step-like memory function is considered as a model for the analysis of rank distributions of words in stochastic symbolic dynamical systems. We prove that the envelope curve for this distribution obeys the power law with the exponent of the order of unity in the case of rather strong persistent correlations. The Zip

A. Morello, W. G. J. Angenent, G. Frossati, L. J. de Jongh

We present the design and construction of a SQUID-based magnetometer for operation down to temperatures T = 10 mK, while retaining the compatibility with the sample holders typically used in commercial SQUID magnetometers. The system is based on a dc-SQUID coupled to a second-order gradiometer. The sample is placed inside the plastic mixing chamber of a dilu

M. Bruinsma, P. Burchat, A. J. Edwards, H. Kagan

To prevent excessive radiation damage to its Silicon Vertex Tracker, the BaBar experiment at SLAC uses a radiation monitoring and protection system that triggers a beam abort whenever radiation levels are anomalously high. The existing system, which employs large area Si PIN diodes as radiation sensors, has become increasingly difficult to operate due to rad

Meng-Jie Huang, Chao-Hsien Kuo, Zhen Ye

In this paper, the propagation of water surface waves over one-dimensional periodic and random bottoms is investigated by the transfer matrix method. For the periodic bottoms, the band structure is calculated, and the results are compared to the transmission results. When the bottoms are randomized, the Anderson localization phenomenon is observed. The theor

Rudolph C. Hwa, C. B. Yang

The recombination model is applied to the production of phi and Omega at all pt in central Au+Au collisions. Since no light quarks are involved in the hadronization, those hidden-strange particles present a clean slate for the study of the role of strange quarks in large-pt physics. We find that shower s quarks have negligible effect for pt<6 GeV/c, in which

I. J. Thompson, F. M. Nunes, B. V. Danilin

FaCE is a self contained programme, with namelist input, that solves the three body Faddeev equations. It enables the inclusion of excitation of one of the three bodies, whilst the other two remain inert. It is particularly useful for obtaining the binding energies and bound state structure compositions of light exotic nuclei treated as three-body systems, g

H. Garcilazo M. T. Pena

Relativistic effects in a three-body calculation of the $np\toηd$ process are considered. Relativistic effects on the range and strength of the pion exchange contribution to the reaction mechanism may be large, but boost effects of the two-body interactions are negligible. The relativistic calculation confirms previous non-relativistic results, showing that

A. Deloff

We present a three-body formalism describing final-state interaction effects. The three-body enhancement factor is derived by expanding the complete three-particle wave function in hyperspherical harmonics.

M. J. Tannenbaum

Results on physics at RHIC using outgoing leptons and photons will be presented from Au+Au collisions at nucleon-nucleon c.m. energies $\sqrt{s_{NN}}=130$ and 200 GeV and from p-p collisions at $\sqrt{s}=200$ GeV. Introduction and motivation will be presented both from the theoretical and experimental perspectives. Topics include open charm production via si

R. Klages, I. F. Barna, L. Matyas

We consider a particle that is subject to a constant force and scatters inelastically on a vibrating periodically corrugated floor. At small friction and small radius of the circular scatterers the dynamics is dominated by resonances forming spiral structures in phase space. These spiral modes lead to pronounced maxima and minima in the diffusion coefficient

R. K. Saxena, A. M. Mathai, H. J. Haubold

We present an analytic proof of the integrals for astrophysical thermonuclear functions which are derived on the basis of Boltzmann-Gibbs statistical mechanics. Among the four different cases of astrophysical thermonuclear functions, those with a depleted high-energy tail and a cut-off at high energies find a natural interpretation in q-statistics.

R. K. Saxena, A. M. Mathai, H. J. Haubold

In earlier papers Saxena et al. (2002, 2003) derived the solutions of a number of fractional kinetic equations in terms of generalized Mittag-Leffler functions which extended the work of Haubold and Mathai (2000). The object of the present paper is to investigate the solution of a unified form of fractional kinetic equation in which the free term contains an

R. K. Saxena, A. M. Mathai, H. J. Haubold

In a recent paper, Saxena et al. [1] developed the solutions of three generalized fractional kinetic equations in terms of Mittag-Leffler functions. The object of the present paper is to further derive the solution of further generalized fractional kinetic equations. The results are obtained in a compact form in terms of generalized Mittag-Leffler functions.

Nikolai Filonov, Frederic Klopp

The purpose of this paper is to prove that the spectrum of an isotropic Maxwell operator with electric permittivity and magnetic permeability that are periodic along certain directions and tending to a constant super-exponentially fast in the remaining directions is purely absolutely continuous. The basic technical tools is a new ``operatorial&#39;&#39; iden

John Cardy

We consider network models of quantum localisation in which a particle with a two-component wave function propagates through the nodes and along the edges of an arbitrary directed graph, subject to a random SU(2) rotation on each edge it traverses. The propagation through each node is specified by an arbitrary but fixed S-matrix. Such networks model localisa

M. C. Valsakumar, A. Rajan Nambiar, P. Rameshan

Discrete time evolution of one-dimensional maps is embedded in continuous time by truncating the Taylor series expansion of the time evolution operator to a finite order N. Truncations with N > 4 leads to unconditional instability. Generalization of the truncated models with N = 3 and 4 shows dynamical behaviour characteristic of systems with a riddled param

Kazuhiro Hikami, Anatol N. Kirillov

We study certain connections between the quantum invariants of the torus knots T_{3,2^k} and some q-series identities. In particular, we obtain new generalizations of Slater&#39;s identities (83) and (86).

Martin Bojowald, Alexei Kotov, Thomas Strobl

Chern-Simons gauge theories in 3 dimensions and the Poisson Sigma Model (PSM) in 2 dimensions are examples of the same theory, if their field equations are interpreted as morphisms of Lie algebroids and their symmetries (on-shell) as homotopies of such morphisms. We point out that the (off-shell) gauge symmetries of the PSM in the literature are not globally

Jana Rodriguez Hertz

On a Peano continuum, all local stable and unstable components of a continuum-wise expansive homeomorphism are non trivial. In particular, there is sensitive dependence on initial conditions. This generalizes results in \cite{h,l} about lack of Lyapunov stable points (weak sinks) and existence of non trivial stable and unstable components for expansive homeo

Menahem Kojman, Wieslaw Kubis, Saharon Shelah

For an infinite cardinal mu, MAD(mu) denotes the set of all cardinalities of nontrivial maximal almost disjoint families over mu. Erdos and Hechler proved the consistency of [mu in MAD(mu)] for a singular cardinal mu and asked if it was ever possible for a singular mu that [mu notin MAD(mu)], and also whether 2^{cf(mu)}<mu ===> [mu in MAD(mu)] for every sing

Jeanne N. Clelland, Christopher G. Moseley

We define the notion of sub-Finsler geometry as a natural generalization of sub-Riemannian geometry with applications to optimal control theory. We compute a complete set of local invariants, geodesic equations, and the Jacobi operator for the three-dimensional case and investigate homogeneous examples.

Thomas Jech, Saharon Shelah

For every regular cardinal kappa there exists a simple complete Boolean algebra with kappa generators.

Jesse I. Deutsch

Recently the author used certain quaternion orders to demonstrate the universality of some quaternary quadratic forms. Here a further study is done on one of these orders analogous to Hurwitz&#39;s proof of the formula for the number of representations of a positive integer by sums of four squares using quaternions. The result is the formula for the number o

Ching-Kang Ing

We consider the problem of choosing the optimal (in the sense of mean-squared prediction error) multistep predictor for an autoregressive (AR) process of finite but unknown order. If a working AR model (which is possibly misspecified) is adopted for multistep predictions, then two competing types of multistep predictors (i.e., plug-in and direct predictors)

István Berkes, Lajos Horváth

We propose a class of estimators for the parameters of a GARCH(p,q) sequence. We show that our estimators are consistent and asymptotically normal under mild conditions. The quasi-maximum likelihood and the likelihood estimators are discussed in detail. We show that the maximum likelihood estimator is optimal. If the tail of the distribution of the innovatio

Anton Schick, Wolfgang Wefelmeyer

Suppose we observe an invertible linear process with independent mean-zero innovations and with coefficients depending on a finite-dimensional parameter, and we want to estimate the expectation of some function under the stationary distribution of the process. The usual estimator would be the empirical estimator. It can be improved using the fact that the in

Danilo Mercurio, Vladimir Spokoiny

This paper offers a new approach for estimating and forecasting the volatility of financial time series. No assumption is made about the parametric form of the processes. On the contrary, we only suppose that the volatility can be approximated by a constant over some interval. In such a framework, the main problem consists of filtering this interval of time

Jesse I. Deutsch

Quadratic forms over Z that represent all positive integers are called universal. Starting with Ramanujan, 54 universal quaternary quadratic forms without cross product terms were discovered. The form that is the sum of four squares was proved universal by Hurwitz using a special ring of quaternions. Here seven other quaternary quadratic forms are shown univ

T. Tony Cai, Mark G. Low

The minimax theory for estimating linear functionals is extended to the case of a finite union of convex parameter spaces. Upper and lower bounds for the minimax risk can still be described in terms of a modulus of continuity. However in contrast to the theory for convex parameter spaces rate optimal procedures are often required to be nonlinear. A construct

Benoit Daniel

We give a necessary and sufficient condition for an n-dimensional Riemannian manifold to be isometrically immersed in S^n x R or H^n x R in terms of its first and second fundamental forms and of the projection of the vertical vector field on its tangent plane. We deduce the existence of a one-parameter family of isometric minimal deformations of a given mini

Yannick Baraud

Starting from the observation of an R^n-Gaussian vector of mean f and covariance matrix σ^2 I_n (I_n is the identity matrix), we propose a method for building a Euclidean confidence ball around f, with prescribed probability of coverage. For each n, we describe its nonasymptotic property and show its optimality with respect to some criteria.

Eric D. Kolaczyk, Robert D. Nowak

We describe here a framework for a certain class of multiscale likelihood factorizations wherein, in analogy to a wavelet decomposition of an L^2 function, a given likelihood function has an alternative representation as a product of conditional densities reflecting information in both the data and the parameter vector localized in position and scale. The fr

Chuu-Lian Terng, Erxiao Wang

Let $σ$ be an involution of a real semi-simple Lie group $U$, $U_0$ the subgroup fixed by $σ$, and $U/U_0$ the corresponding symmetric space. Ferus and Pedit called a submanifold $M$ of a rank $r$ symmetric space $U/U_0$ a {\it curved flat} if $T_pM$ is tangent to an $r$-dimensional flat of $U/U_0$ at $p$ for each $p\in M$. They noted that the equation for c

Laura Felicia Matusevich, Ezra Miller, Uli Walther

We analyze the behavior of the holonomic rank in families of holonomic systems over complex algebraic varieties by providing homological criteria for rank-jumps in this general setting. Then we investigate rank-jump behavior for hypergeometric systems H_A(β) arising from a d x n integer matrix A and a parameter β\in \CC^d. To do so we introduce an Euler-Kosz

Robert W. Baddeley, Cheryl E. Praeger, Csaba Schneider

We study Cartesian decompositions of sets that are acted upon intransitively by innately transitive permutation groups. We prove that such groups have at most three orbits on such a decomposition. A consequence of this result is that if $G$ is an innately transitive subgroup of a wreath product in product action then the natural projection of $G$ into the to

Gianluca Mandanici, Antonino Marciano

A quantum theory of noncommutative fields was recently proposed by Carmona, Cortez, Gamboa and Mendez (hep-th/0301248). The implications of the noncommutativity of the fields, intended as the requirements $[\phi,\phi^{+}]=\theta\delta^{3}(x-x^{\prime}), [\pi,\pi^{+}]=B\delta^{3}(x-x^{\prime}) $, were analyzed on the basis of an analogy with previous results

N. Kitanine, J. M. Maillet, N. A. Slavnov, V. Terras

We derive a new representation for spin-spin correlation functions of the finite XXZ spin-1/2 Heisenberg chain in terms of a single multiple integral, that we call the master equation. Evaluation of this master equation gives rise on the one hand to the previously obtained multiple integral formulas for the spin-spin correlation functions and on the other ha

Stefano Bellucci, Armen Nersessian, Armen Yeranyan

We construct the quantum oscillator interacting with a constant magnetic field on complex projective spaces $\DC P^N$, as well as on their non-compact counterparts, i. e. the $N-$dimensional Lobachewski spaces ${\cal L}_N$. We find the spectrum of this system and the complete basis of wavefunctions. Surprisingly, the inclusion of a magnetic field does not yi

N. Tetradis

We derive exact solutions of the Einstein equations in the context of the Randall-Sundrum model with matter on the brane and in the bulk. We present two models in which the brane moves within a time-dependent bulk. We study the cosmological evolution on the brane. Our solutions display novel behaviour, such as an expansion driven only by the bulk matter and

Arkady L. Kholodenko

The concepts of apartments and buildings were suggested by Tits for description of the Weyl-Coxeter reflection groups. We use these and many additional facts from the theory of reflection and pseudo-reflection groups along with results from the algebraic and symplectic geometry of toric varieties in order to obtain the tachyon-free Veneziano-like multipartic

S. Heinemeyer

We review the theoretical status and the future perspectives of the most important electroweak precision observables in the MSSM. This comprises the mass of the W boson, M_W, the effective leptonic mixing angle, sin^2(theta_eff), the mass of the lightest MSSM Higgs boson, m_h, and the anomalous magnetic moment of the muon, a_μ. The impact of the parametric u

Shmuel Nussinov

The high degeneracy of KK modes in models which have bulk axions moving in some extra, compact dimensions which are larger than O (Angstrom)strongly tightens the supernova upper bounds on the axion photon coupling making axions practically unobservable. Conversely, discovering axions directly or indirectly will exclude such models. These drastic conclusions

S. Nasri, J. Schechter, S. Moussa

The &#34;complementary&#34; Ansatz, Tr$(M_ν)=0$, where $M_ν$ is the prediagonal neutrino mass matrix, seems a plausible approximation for capturing in a self-contained way some of the content of Grand Unification. We study its consequences in the form of relations between the neutrino masses and CP violation phases.

Jeppe R. Andersen

The high energy limit of scattering processes in QCD is, at least on the purely theoretical level, described by the BFKL equation. However, many phenomenological studies of BFKL fail miserably when confronted with data. In this talk we will briefly review the application of (LL) BFKL in phenomenology, and critically examine the application of LL eigenfunctio

Matthias Steinhauser

In this contribution the first next-to-next-to-leading order corrections to the branching ratio ${BR}(\bar{B}\to X_sγ)$ are discussed. This includes the completion of the matching part and the fermionic corrections to the most important operator matrix elements.

Jose Santiago

We review the very stringent lower bounds on the string scale that arise from flavor considerations in models with intersecting branes. Despite the absence of a realistic flavor structure at tree level, flavor changing interactions induce a non-trivial pattern of fermion masses and mixing angles when quantum corrections are taken into account. The resulting

M. N. Chernodub, B. L. Ioffe

A qualitative analysis of the chiral phase transition in QCD with two massless quarks and non--zero baryon density is performed. It is assumed that at zero baryonic density, $ρ=0$, the temperature phase transition is of the second order. Due to a specific power dependence of baryon masses on the chiral condensate the phase transition becomes of the first ord

Tetsuo Nishikawa

We derive a QCD sum rule for the flavour-singlet axial coupling constant $g_A^{(0)}$ from a two point correlation function of flavour-singlet axial vector currents in a one-nucleon state. In evaluating the correlation function by an operator product expansion we take into account the terms up to dimension 6. This correlation function receives an additional t

Richard F. Lebed

Excited baryons may be analyzed in the 1/N_c expansion as true resonances in scattering amplitudes. The key idea making this program possible is a generalization of methods originally applied to chiral soliton models in the 1980&#39;s. One finds model-independent relations among amplitudes that impose mass and width degeneracies among resonances of various q

V. Schegelsky, A. Sarantsev, V. Nikonov, A. Anisovich

This paper was withdrawn by arXiv administrators upon request of the Chairperson and Spokesperson of the L3 Collaboration.

V. A. Schegelsky, A. V. Sarantsev, V. A. Nikonov, A. V. Anisovich

This paper was withdrawn by arXiv administrators upon request of the Chairperson and Spokesperson of the L3 Collaboration.

P. Butera, M. Comi

We have extended, from order 12 through order 25, the high-temperature series expansions (in zero magnetic field) for the spin-spin correlations of the spin-S Ising models on the square, simple-cubic and body-centered-cubic lattices. On the basis of this large set of data, we confirm accurately the validity of the scaling and universality hypotheses by resum

M. Iwasaki

We report the measurements of electroweak penguin processes b->d,s gamma and b->sl+l- at the Belle experiment. The analyses are based on 152 million BB-bar events collected at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- asymmetric-energy collider. The b->d gamma transition is studied through exclusive decays: B0->rho0 gamma, B0->omega

Siegfried Bethke

Studies of hadronic final states of $e^+e^-$ annihilations at LEP are reviewed. The topics included cover hadronic event shapes, measurements of $α_s$, determinations of QCD colour factors and tests of the non-Abelian gauge structure of QCD, differences between quark and gluon jets, QCD with heavy quarks and selected results of two-photon scattering processe

G. S. Bisnovatyi-Kogan, V. N. Rudenko

Astrophysical sources of high frequency gravitational radiation are considered in association with a new interest to very sensitive HFGW receivers required for the laboratory GW Hertz experiment. A special attention is paid to the phenomenon of primordial black holes evaporation. They act like black body to all kinds of radiation, including gravitons, and, t

J. Fernando Barbero G., Guillermo A. Mena Marugan, Eduardo J. S. Villaseñor

We discuss the connection between the Fock space introduced by Ashtekar and Pierri for Einstein-Rosen waves and its perturbative counterpart based on the concept of particle that arises in linearized gravity with a de Donder gauge. We show that the gauge adopted by Ashtekar and Pierri is a generalization of the de Donder gauge to full (i.e. non-linearized) c

Valdis Vitolins

The paper proposes a new methodology for defining business process measures and their computation. The approach is based on metamodeling according to MOF. Especially, a metamodel providing precise definitions of typical process measures for UML activity diagram-like notation is proposed, including precise definitions how measures should be aggregated for com

Etienne Payet, Fred Mesnard

We present a static analysis technique for non-termination inference of logic programs. Our framework relies on an extension of the subsumption test, where some specific argument positions can be instantiated while others are generalized. We give syntactic criteria to statically identify such argument positions from the text of a program. Atomic left looping

V. Ferrando, C. Tarantini, E. Bellingeri, P. Manfrinetti

Structural and superconducting properties of magnesium diboride thin films grown by pulsed laser deposition on zirconium diboride buffer layers were studied. We demonstrate that the ZrB2 layer is compatible with the MgB2 two step deposition process. Synchrotron radiation measurements, in particular anomalous diffraction measurements, allowed to separate MgB2

R. Saniz, J. E. Medvedeva, Lin-Hui Ye, T. Shishidou

We report a first-principles density-functional calculation of the electronic structure and properties of the recently discovered superconducting beta-pyrochlore oxide KOs_2O_6. We find that the electronic structure near the Fermi energy E_F is dominated by strongly hybridized Os-5d and O-2p states. A van Hove singularity very close to E_F leads to a relativ

Thereza Paiva, R. T. Scalettar, W. Zheng, R. R. P. Singh

We investigate ground state and finite temperature properties of the half-filled Hubbard model on a honeycomb lattice using quantum monte carlo and series expansion techniques. Unlike the square lattice, for which magnetic order exists at T=0 for any non-zero $U$, the honeycomb lattice is known to have a semi-metal phase at small $U$ and an antiferromagnetic

Onuttom Narayan, B. Sriram Shastry

We generalize the Gutzwiller wavefunction for s = 1/2 spin chains to construct a family of wavefunctions for all s > 1/2. Through numerical simulations, we demonstrate that the spin spin correlation functions for all s decay as a power law with logarithmic corrections. This is done by mapping the model to a classical statistical mechanical model, which has c

B. Szafran, F. M. Peeters, S. Bednarek

Few-electron systems confined in a quantum dot laterally coupled to a surrounding quantum ring in the presence of an external magnetic field are studied by exact diagonalization. The distribution of electrons between the dot and the ring is influenced by the relative strength of the dot and ring confinement, the gate voltage and the magnetic field which indu

Sadhan K. Adhikari

Using variational and numerical solutions of the mean-field Gross-Pitaevskii equation we show that a bright soliton can be stabilized in a trapless three-dimensional attractive Bose-Einstein condensate (BEC) by a rapid periodic temporal modulation of scattering length alone by using a Feshbach resonance. This scheme also stabilizes a rotating vortex soliton

Andrew N. Jordan, Markus Buttiker

We propose a quantum nondemolition measurement using a kicked two-state system (qubit). By tuning the waiting time between kicks to be the qubit oscillation period, the kicking apparatus performs a nondemolition measurement. While dephasing is unavoidable, the nondemolition measurement can (1) slow relaxation of diagonal density matrix elements, (2) avoid de

J. S. Aldridge, A. N. Cleland

We report quantitative experimental measurements of the nonlinear response of a radiofrequency mechanical resonator, with very high quality factor, driven by a large swept-frequency force. We directly measure the noise-free transition dynamics between the two basins of attraction that appear in the nonlinear regime, and find good agreement with those predict

M. R. Evans, Satya N. Majumdar, R. K. P. Zia

We study a class of mass transport models where mass is transported in a preferred direction around a one-dimensional periodic lattice and is globally conserved. The model encompasses both discrete and continuous masses and parallel and random sequential dynamics and includes models such as the Zero-range process and Asymmetric random average process as spec

A. A. Sahakyan, S. K. Nikoghosyan, H. N. Yeritsyan, G. V. Grigoryan

The Josephson vortices dynamic in superconducting $YBa_2Cu_3O_x$ ceramics was studied in frequency range 0.01-0.5 Hz by ac susceptibility measurements in non complete magnetic flux penetration regime. We have found that with the increase of magnetic field frequency starting from 0.01 Hz the ac magnetic response shows complex frequency dependence: in one half

A. V. Sologubenko, R. Dell&#39;Amore, H. R. Ott, P. Millet

We present the results of measurements of the thermal conductivity of Cu2Te2O5Br2, a compound where tetrahedra of Cu^{2+} ions carrying S=1/2 spins form chains along the c-axis of the tetragonal crystal structure. The thermal conductivity kappa was measured along both the c- and the a-direction as a function of temperature between 3 and 300 K and in external

M. Mercedes Calbi, Flavio Toigo, Milton W. Cole

We analyze the relationship between our group&#39;s results and those of three recent papers about gases in interstitial channels within nanotube bundles. In particular, we explain the relation between our prediction about bundle dilation upon interstitial adsorption (questioned in some way in these works) and their results.

Victor Gubanov, Sergiy Koryakov

It was suggested method of constructing of irreducible projective representations in different points of Brilluin zone. Points Γ, Λ, Z, S, A, Σ, M, V, R, and X of space symmetry groups $P4_{1}2_{1}2$ and $P4_{3}2_{1}2$ were examined. At each of these points one- and two-valued irreducible projective representations of wave vector groups were constructed for

Y. S. Gui, C. R. Becker, N. Dai, J. Liu

We have investigated beating patterns in Shubnikov-de Haas oscillations for HgTe/Hg_{0.3}Cd_{0.7}Te(001) quantum wells with electron densities of 2 to 3 X 10^{12} cm^{-2}. Up to 12 beating nodes have been observed at magnetic fields between 0.9 and 6 T. Zero magnetic field spin-orbit splitting energies up to 30 meV have been directly determined from the node

Anjana Bagga, P. K. Chattopadhyay, Subhasis Ghosh

The effect of non-sphericity of the quantum dot on the eigenvalues and eigenfunctions has been investigated for the case of both the finite and infinite barrier. The ground and excited state energies have been calculated for prolate and oblate spheroids as a function of eccentricity of the spheroid. The analytic wavefunctions giving the admixture of higher a

J. P. Carbotte, E. Schachinger

We consider the optical conductivity of a d-wave BCS superconductor in the presence of a non-equilibrium distribution of excess quasiparticles. Two different simplified models used in the past for the s-wave case are considered and results compared. In the $T^\ast$-model of Parker the excess quasiparticles are assumed to be in a thermal distribution at some

Ch. C. Moustakidis

A theoretical treatment of the static structure factor $S(k)$ of a Bose gas is attempted. The low order expansion theory is implemented for the construction of the two body density distribution, while various trial functions for the radial distribution function $g(r)$ are used. $g(r)$ introduces the atomic correlations and describes the departure from the no

I. Travenec

Shot noise and higher current moments T_M=<Tr (t^+t)^M> are studied within the Anderson model of disordered conductors in dimensions d= 2, 3 and 4. Here t denotes a transmission matrix. We calculate the conductance G=T_1, shot noise S=T_1-T_2, Fano factor F=S/G and ratios C_M=T_M/G, and we show indications that all of them are as good order parameters as the

Joachim Sjostrand, Jochen Walter, David Haviland, Hans Hansson

We have studied the switching behaviour of a small capacitance Josephson junction both in experiment, and by numerical simulation of a model circuit. The switching is a comples process involving the transition between two dynamical states of the non-linear circuit, arising from a frequency dependent damping of the Josephson junction. We show how a specific t

Y. Vaills, T. Qu, M. Micoulaut, F. Chaimbault

The Brillouin elastic free energy change $DF$ between thermally annealed and quenched $(Na_2O)_x(SiO_2)_{1-x}$ glasses is found to decrease linearly at $x > 0.23$ (floppy phase), and to nearly vanish at $x < 0.18$ (stressed- rigid phase). The observed $D F(x)$ variation closely parallels the mean-field floppy mode fraction $f(x)$ in random networks, and fixe

J. C. Cuevas, W. Belzig

We present a comprehensive theoretical analysis of the dc transport properties of superconducting point contacts. We determine the full counting statistics for these junctions, which allows us to calculate not only the current or the noise, but all the cumulants of the current distribution. We show how the knowledge of the statistics of charge transfer provi

Subhasis Ghosh, Niladri Sarkar

We present an experimental investigation of heavy doping-induced many-body effects such as band gap narrowing(BGN) and Fermi edge singularity(FES) in Al$_x$Ga$_{1-x}$As using photoluminescence(PL) spectroscopy. The band-to-band transition energy shifts to lower energies and FES-like feature in PL spectra grows with increasing electron concentration. We show

S. V. Halilov, D. J. Singh, M. Gupta, R. Gupta

The stability and bonding of the ternary complex K$_2$PtCl$_6$ structure hydrides is discussed using first principles density functional calculations. The cohesion is dominated by ionic contributions, but ligand field effects are important, and are responsible for the 18-electron rule. Similarities to oxides are discussed in terms of the electronic structure

T. Nakajima, H. Yoshizawa, Y. Ueda

The discovery of novel structural and physical properties in the $A$-site ordered manganite $R$BaMn$_{2}$O$_{6}$ ($R$ = Y and rare earth elements) has demanded new comprehension about perovskite manganese oxides. In the present study, the $A$-site disordered form, $R_{0.5}$Ba$_{0.5}$MnO$_{3}$, has been investigated and compared with both $R$BaMn$_{2}$O$_{6}$

Nobuo Furukawa, Yukitoshi Motome, Naoto Nagaosa

We discuss the origin of the reentrant behaviors of insulating states above the Curie temperature of the colossal magnetoresistance manganites. We consider a system where charge ordering and ferromagnetism compete with each other. In the presence of randomness which pins charge order fluctuations, entropy-driven reentrant behaviors will appear, which explain

Tarun Kanti Ghosh

The Hanbury Brown-Twiss experiment has proved to be an effective means of measuring two-point correlation function of identical particles. We analyze experimental observation of stripes formation of a phase fluctuating Bose-Einstein condensates in a highly elongated 3D traps [Dettmer {\em et al.}, Phys. Rev. Lett. {\bf 87}, 160406 (2001)] by means of axial t

V. I. Yukalov, E. P. Yukalova

The main part of this review is devoted to the comprehensive description of coherent radiation by nuclear spins. The theory of nuclear spin superradiance is developed and the experimental observations of this phenomenon are considered. The intriguing problem of how coherence develops from initially incoherent quantum fluctuations is analysed. All main types

B. Mirza, M. R. Bakhtiari

By using a decomposition of the transfer matrix of the two dimensional $q$-state Potts Model to $V^{\prime}_1$ and $V_2$ its determinant is calculated. Our result is a proof for a conjectured formula by Chang and Shrock in [14].

D. M. Basko, V. E. Kravtsov

We study conductance through a quantum dot under Coulomb blockade conditions in the presence of an external periodic perturbation. The stationary state is determined by the balance between the heating of the dot electrons by the perturbation and cooling by electron exchange with the cold contacts. We show that Coulomb blockade peak can have a peculiar shape

Shih-Jye Sun, Song-Shien Cheng, Hsiu-Hau Lin

We studied the exchange interactions mediated by polarized itinerant carriers in diluted magnetic semiconductor (DMS) junction. In contrast to the ordinary RKKY oscillations, the induced moment possesses an interesting spiral motion, accompanied with angular oscillations. The spiral motion remains robust in the entire $T<T_{c}$ regime while the oscillatory m