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Related papers: Effective $\sigma$ Model Formulation for Two Inter…

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We suggest a novel nonlinear $\sigma$-model for the description of disordered superconductors. The main distinction from existing models lies in the fact that the saddle point equation is solved non-perturbatively in the superconducting…

Superconductivity · Physics 2009-10-31 I. V. Yurkevich , Igor V. Lerner

We present a theoretical framework for evaluating effective interactions between localized spins mediated by itinerant electrons in double-exchange models. Performing the expansion with respect to the spin-dependent part of the electron…

Strongly Correlated Electrons · Physics 2016-04-29 Hiroaki Ishizuka , Yukitoshi Motome

We numerically investigate the transport properties of disordered interacting electrons in three dimensions in the metallic as well as in the insulating phases. The disordered many-particle problem is modeled by the quantum Coulomb glass…

Mesoscale and Nanoscale Physics · Physics 2016-04-20 Thomas Vojta , Frank Epperlein

Self-consistent theory of electron localization in disordered systems is generalized for the case of interacting electrons. We propose and critically compare a number of possible self-consistency schemes which take into account the lowest…

Condensed Matter · Physics 2008-02-03 E. Z. Kuchinskii , M. V. Sadovskii , V. G. Suvorov

The theory of correlated electron systems is formulated in a form which allows to use as a reference point an ab initio band structure theory (AIBST). The theory is constructed in two steps. As a first step the total Hamiltonian is…

Strongly Correlated Electrons · Physics 2007-05-23 Igor Sandalov , Borje Johansson , Olle Eriksson

An effective field theory for clean electron systems is developed in analogy to the generalized nonlinear sigma-model for disordered interacting electrons. The physical goal is to separate the soft or massless electronic degrees of freedom…

Strongly Correlated Electrons · Physics 2013-10-01 D. Belitz , T. R. Kirkpatrick

A two-band model of a disordered semiconductor is used to analyze dynamical interaction induced weakening of localization in a system that is accessible to experimental verification. The results show a dependence on the sign of the…

Disordered Systems and Neural Networks · Physics 2009-10-31 D. Brinkmann , J. E. Golub , S. W. Koch , P. Thomas , K. Maschke , I. Varga

We develop an Effective Medium Theory to study the electrical transport properties of disordered graphene. The theory includes non-linear screening and exchange-correlation effects allowing us to consider experimentally relevant strengths…

Mesoscale and Nanoscale Physics · Physics 2009-06-20 Enrico Rossi , S. Adam , S. Das Sarma

The effect of a Zeeman magnetic field coupled to the spin of the electrons on the conducting properties of the disordered Hubbard model is studied. Using the Determinant Quantum Monte Carlo method, the temperature- and magnetic-field-…

Strongly Correlated Electrons · Physics 2009-11-10 P. J. H. Denteneer , R. T. Scalettar

We calculate the corrections to the conductivity and compressibility of a disordered metal when the mean free path is smaller than the screening length. Such a condition is shown to be realized for low densities and large disorder. Analysis…

Strongly Correlated Electrons · Physics 2009-10-31 Qimiao Si , C. M. Varma

The present paper is devoted to the study of a simple model of interacting electrons in a random background. In a large interval $\Lambda$, we consider $n$ one dimensional particles whose evolution is driven by the Luttinger-Sy model, i.e.,…

Mathematical Physics · Physics 2014-08-26 Frédéric Klopp , Nikolaj Veniaminov

We solve the double exchange model in the presence of arbitrary substitutional disorder by using a self consistently generated effective Hamiltonian for the spin degrees of freedom. The magnetic properties are studied through classical…

Strongly Correlated Electrons · Physics 2009-11-10 Sanjeev Kumar , Pinaki Majumdar

We introduce a model of a nonlinear double-barrier structure, to describe in a simple way the effects of electron-electron scattering while remaining analytically tractable. The model is based on a generalized effective-mass equation where…

Condensed Matter · Physics 2009-10-28 Enrique Diez , Angel Sanchez , Francisco Dominguez-Adame

It has been argued that despite remarkable success, existing random matrix theories are not adequate to describe disordered conductors in the metallic regime, due to the presence of certain two-body interactions in the effective Hamiltonian…

Condensed Matter · Physics 2007-05-23 K. A. Muttalib

We study the relaxation of a non-equilibrium carrier distribution under the influence of the electron-electron interaction in the presence of disorder. Based on the Anderson model, our Hamiltonian is composed from a single particle part…

Disordered Systems and Neural Networks · Physics 2008-02-15 Peter Bozsoki , Imre Varga , Henning Schomerus

We study integrable models for electrons in metals when the single particle spectrum is discrete. The electron-electron interactions are BCS-like pairing, Coulomb repulsion, and spin exchange coupling. These couplings are, in general,…

Superconductivity · Physics 2011-07-19 Luigi Amico , Antonio Di Lorenzo , Andreas Osterloh

We develop an effective theory for heavy baryons and their excited states. The approach is based on the contracted O(8) symmetry recently shown to emerge from QCD for these states in the combined large N_c and heavy quark limits. The…

High Energy Physics - Phenomenology · Physics 2010-11-19 Chi-Keung Chow , Thomas D. Cohen , Boris A. Gelman

We calculate two-point energy level correlation function in weakly disorderd metallic grain with taking account of localization corrections to the universal random matrix result. Using supersymmetric nonlinear sigma model and exactly…

Disordered Systems and Neural Networks · Physics 2009-11-07 Naohiro Mae , Shinji Iida

In these lectures, given at the NATO ASI at Windsor (2001), applications of the replicas nonlinear sigma model to disordered systems are reviewed. A particular attention is given to two sets of issues. First, obtaining non-perturbative…

Disordered Systems and Neural Networks · Physics 2007-05-23 Igor V. Lerner

We present the effective theory for low energy dynamics of a two-dimensional interacting electrons in the presence of a weak short-range disorder and a weak perpendicular magnetic field, the filling factor $\nu \gg 1$. We investigate the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 I. S. Burmistrov