22-GHz Modulation Bandwidth of Long Cavity DBR Laser by Using a Weakly Laterally Coupled Grating Fabricated by Focused Ion Beam Lithography

A 22-GHz directly modulated 3-dB bandwidth could be obtained by 1.3-mm-long weakly laterally coupled distributed Bragg reflector lasers fabricated by focused ion beam lithography. In addition to a high bandwidth, the lasers show a stable emission spectrum with side-mode suppression ratios of more than 40 dB and output powers exceeding 20 mW

The Generalization of the Decomposition of Functions by Energy Operators

This work starts with the introduction of a family of differential energy operators. Energy operators ($Psi_R^+$, $Psi_R^-$) were defined together with a method to decompose the wave equation in a previous work. Here the energy operators are defined following the order of their derivatives ($Psi_k^+$, $Psi_k^-$, k = {0,1,2,..}). The main part of the work is to demonstrate that for any smooth real-valued function f in the Schwartz space ($S^-(R)$), the successive derivatives of the n-th power of f (n in Z and n not equal to 0) can be decomposed using only $Psi_k^+$ (Lemma) or with $Psi_k^+$, $Psi_k^-$ (k in Z) (Theorem) in a unique way (with more restrictive conditions). Some properties of the Kernel and the Image of the energy operators are given along with the development. Finally, the paper ends with the application to the energy function.Comment: The paper was accepted for publication at Acta Applicandae Mathematicae (15/05/2013) based on v3. v4 is very similar to v3 except that we modified slightly Definition 1 to make it more readable when showing the decomposition with the families of energy operator of the derivatives of the n-th power of

Be a Fulbright Scholar—Lessons and Experiences of AIS Fulbright Scholars

To achieve a truly global perspective in information systems (IS) that enhances education and research, IS academics can do more than study and teach global IS topics. We encourage IS academics to engage in an international immersion experience themselves. The article describes experiences of Fulbright Scholars, and argues for the need of more global education for IS academics. These views were presented during a panel session at the Americas Conference on Information Systems (AMCIS) 2012. The panelists touched on logistical issues such as grant application, living conditions, working with a host institution’s faculty and students, and receiving support from their home university. Participants shared their experiences in India, Poland, Portugal, the Azores, Mongolia, and Nepal. The article concludes with lessons learned

Isovector part of nuclear energy density functional from chiral two- and three-nucleon forces

A recent calculation of the nuclear energy density functional from chiral two- and three-nucleon forces is extended to the isovector terms pertaining to different proton and neutron densities. An improved density-matrix expansion is adapted to the situation of small isospin-asymmetries and used to calculate in the Hartree-Fock approximation the density-dependent strength functions associated with the isovector terms. The two-body interaction comprises of long-range multi-pion exchange contributions and a set of contact terms contributing up to fourth power in momenta. In addition, the leading order chiral three-nucleon interaction is employed with its parameters fixed in computations of nuclear few-body systems. With this input one finds for the asymmetry energy of nuclear matter the value $A(\rho_0) \simeq 26.5\,$MeV, compatible with existing semi-empirical determinations. The strength functions of the isovector surface and spin-orbit coupling terms come out much smaller than those of the analogous isoscalar coupling terms and in the relevant density range one finds agreement with phenomenological Skyrme forces. The specific isospin- and density-dependences arising from the chiral two- and three-nucleon interactions can be explored and tested in neutron-rich systems.Comment: 14 pages, 7 figures, to be published in European Physical Journal

Анализ отдаленных результатов санаторно-курортного лечения детей с реактивными артритами

На підставі вивчення віддалених результатів санаторно-курортного лікування з використанням клініко-лабораторних і функціональних параметрів 50 дітей з реактивними артритами встановлений сприятливий ефект в перебігу захворювання, що виявлялося відсутністю загострень, поліпшенням клінічної картини захворювання, зменшенням проявів суглобового синдрому, підвищенням функціональної активності нервово-м'язового апарату, поліпшенням показників якості життя.On the basis of study of remote results of resort medical treatment with the use of clinics,-laboratory and functional at 50 children with reactive arthritics a favorable effect in the flow of disease is set, that showed up absence of intensifications, improvement of clinical picture of disease, reduction of displays of joint syndrome, rise of functional activity of muscle vehicle, by the improvement of indexes of quality of life

The derivative of the topological susceptibility at zero momentum and an estimate of η′\eta' mass in the chiral limit

The anomaly-anomaly correlator is studied using QCD sum rules. Using the matrix elements of anomaly between vacuum and pseudoscalars $\pi, eta$ and $\eta'$, the derivative of correlator $chi'(0)$ is evaluated and found to be $\approx 1.82 \times 10^{-3}$ GeV$^2$. Assuming that $\chi'(0)$ has no significant dependence on quark masses, the mass of $\eta'$ in the chiral limit is found to be $\approx$723 MeV. The same calculation also yields for the singlet pseudoscalar decay constant in the chiral limit a value of $\approx 178$ MeV.Comment: LaTeX, 7 pages, 2 figures, uses cernrep.cls (included

Large Kinetic Power in FRII Radio Jets

We investigate the total kinetic powers (L_{j}) and ages (t_{age}) of powerful jets of four FR II radio sources (Cygnus A, 3C 223, 3C 284, and 3C 219) by the detail comparison of the dynamical model of expanding cocoons with observed ones. It is found that these sources have quite large kinetic powers with the ratio of L_{j} to the Eddington luminosity (L_{Edd}) resides in $0.02 <L_{j}/L_{Edd} <10$. Reflecting the large kinetic powers, we also find that the total energy stored in the cocoon (E_{c}) exceed the energy derived from the minimum energy condition (E_{min}): $2< E_{c}/E_{min} <160$. This implies that a large amount of kinetic power is carried by invisible components such as thermal leptons (electron and positron) and/or protons.Comment: 5 pages, accepted for publication in Astrophysics and Space Scienc

Primordial black hole production due to preheating

During the preheating process at the end of inflation the amplification of field fluctuations can lead to the amplification of curvature perturbations. If the curvature perturbations on small scales are sufficiently large, primordial black holes (PBHs) will be overproduced. In this paper we study PBH production in the two-field preheating model with quadratic inflaton potential. We show that for many values of the inflaton mass m, and coupling g, small scale perturbations will be amplified sufficiently, before backreaction can shut off preheating, so that PBHs will be overproduced during the subsequent radiation dominated era.Comment: 5 pages, 3 eps figures. Minor changes to match version to appear in PRD as a rapid communicatio

Nonlinear evolution of the momentum dependent condensates in strong interaction: the ``pseudoscalar laser''

We discuss the relaxation of the scalar and pseudoscalar condensates after a rapid quench from an initial state with fluctuations. If we include not only the zero-mode but also higher modes of the condensates in the classical evolution, we observe parametric amplification of those ``hard'' modes. Thus, they couple nonlinearly to the ``soft'' modes. As a consequence, domains of coherent pi-field emerge long after the initial spinodal decomposition. The momentum-space distribution of pions emerging from the decay of that momentum-dependent condensate is discussed.Comment: 6 Pages, REVTEX, 8 Figures; one reference and one figure adde