12,342 research outputs found

    Moduli space volume of vortex and localization

    Full text link
    Volume of moduli space of BPS vortices on a compact genus h Riemann surface Sigma_h is evaluated by means of topological field theory and localization technique. Vortex in Abelian gauge theory with a single charged scalar field (ANO vortex) is studied first and is found that the volume of the moduli space agrees with the previous results obtained more directly by integrating over the moduli space metric. Next we extend the evaluation to non-Abelian gauge groups and multi-flavors of scalar fields in the fundamental representation. We find that the result of localization can be consistently understood in terms of moduli matrix formalism wherever possible. More details are found in our paper in Prog.Theor.Phys.126 (2011) 637.Comment: 10 pages, talk at the international conference "quantum theory and symmetries 7" in prague, august 7-13, 201

    Doping dependent quasiparticle band structure in cuprate superconductors

    Full text link
    We present an exact diagonalization study of the single particle spectral function in the so-called t-t'-t''-J model in 2D. As a key result, we find that unlike the `pure' t-J model, hole doping leads to a major reconstruction of the quasiparticle band structure near (pi,0): whereas for the undoped system the quasiparticle states near (pi,0) are deep below the top of the band at (pi/2,pi/2), hole doping shifts these states up to E_F, resulting in extended flat band regions close to E_F and around (pi,0). This strong doping-induced deformation can be directly compared to angle resolved photoemission results on Sr_2 Cu Cl_2 O_2, underdoped Bi2212 and optimally doped Bi2212. We propose the interplay of long range hopping and decreasing spin correlations as the mechanism of this deformation.Comment: 4 pages, Revtex, with 4 embedded eps figures. Hardcopies of figures (or the entire manuscript) can be obtained by e-mail request to [email protected]

    Exact Charged 2-Body Motion and the Static Balance Condition in Lineal Gravity

    Get PDF
    We find an exact solution to the charged 2-body problem in (1+1)(1+1) dimensional lineal gravity which provides the first example of a relativistic system that generalizes the Majumdar-Papapetrou condition for static balance.Comment: latex,7 pages, 2 figure

    Mott transition and ferrimagnetism in the Hubbard model on the anisotropic kagom\'e lattice

    Full text link
    Mott transition and ferrimagnetism are studied in the Hubbard model on the anisotropic kagom\'e lattice using the variational cluster approximation and the phase diagram at zero temperature and half-filling is analyzed. The ferrimagnetic phase rapidly grows as the geometric frustration is relaxed, and the Mott insulator phase disappears in moderately frustrated region, showing that the ferrimagnetic fluctuations stemming from the relaxation of the geometric frustration is enhanced by the electron correlations. In metallic phase, heavy fermion behavior is observed and mass enhancement factor is computed. Enhancement of effective spatial anisotropy by the electron correlations is also confirmed in moderately frustrated region, and its effect on heavy fermion behavior is examined.Comment: 5 pages, 6 figure

    Possibility of synthesizing doubly closed superheavy nucleus

    Get PDF
    The possibility of synthesizing a doubly magic superheavy nucleus, 298114184^{298}114_{184}, is investigated on the basis of fluctuation-dissipation dynamics. In order to synthesize this nucleus, we must generate more neutron-rich compound nuclei because of the neutron emissions from excited compound nuclei. The compound nucleus 304114^{304}114 has two advantages to achieving a high survival probability. First, because of small neutron separation energy and rapid cooling, the shell correction energy recovers quickly. Secondly, owing to neutron emissions, the neutron number of the nucleus approaches that of the double closed shell and the nucleus obtains a large fission barrier. Because of these two effects, the survival probability of 304114^{304}114 does not decrease until the excitation energy E=50E^{*}= 50 MeV. These properties lead to a rather high evaporation reside cross section.Comment: 5 pages, 6 figure

    Systematic perturbation approach for a dynamical scaling law in a kinetically constrained spin model

    Full text link
    The dynamical behaviours of a kinetically constrained spin model (Fredrickson-Andersen model) on a Bethe lattice are investigated by a perturbation analysis that provides exact final states above the nonergodic transition point. It is observed that the time-dependent solutions of the derived dynamical systems obtained by the perturbation analysis become systematically closer to the results obtained by Monte Carlo simulations as the order of a perturbation series is increased. This systematic perturbation analysis also clarifies the existence of a dynamical scaling law, which provides a implication for a universal relation between a size scale and a time scale near the nonergodic transition.Comment: 17 pages, 7 figures, v2; results have been refined, v3; A figure has been modified, v4; results have been more refine
    corecore