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Related papers: Ising Spins on Thin Graphs

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We study the Glauber dynamics of Ising spin models with random bonds, on finitely connected random graphs. We generalize a recent dynamical replica theory with which to predict the evolution of the joint spin-field distribution, to include…

Disordered Systems and Neural Networks · Physics 2015-05-13 A. Mozeika , A. C. C. Coolen

We investigate numerically and analytically Potts models on ``thin'' random graphs -- generic Feynman diagrams, using the idea that such models may be expressed as the N --> 1 limit of a matrix model. The thin random graphs in this limit…

High Energy Physics - Lattice · Physics 2008-11-26 D. A. Johnston , P. Plechac

The phase diagram of the random field Ising model on the Bethe lattice with a symmetric dichotomous random field is closely investigated with respect to the transition between the ferromagnetic and paramagnetic regime. Refining arguments of…

Disordered Systems and Neural Networks · Physics 2009-11-07 Thomas Nowotny , Heiko Patzlaff , Ulrich Behn

We calculate the mean number of metastable states of an Ising ferromagnet on random thin graphs of fixed connectivity c. We find, as for mean field spin glasses that this mean increases exponentially with the number of sites, and is the…

Disordered Systems and Neural Networks · Physics 2009-10-31 Alexandre Lefevre , David S. Dean

We consider ferromagnetic Ising models on graphs that converge locally to trees. Examples include random regular graphs with bounded degree and uniformly random graphs with bounded average degree. We prove that the "cavity" prediction for…

Probability · Mathematics 2016-09-08 Amir Dembo , Andrea Montanari

The competition among spin glass (SG), antiferromagnetism (AF) and local pairing superconductivity (PAIR) is studied in a two-sublattice fermionic Ising spin glass model with a local BCS pairing interaction in the presence of an applied…

Disordered Systems and Neural Networks · Physics 2009-11-11 S. G. Magalhaes , F. M. Zimmer , C. J. Kipper , E. J. Callegari

We revisit classical bounds of M. E. Fisher on the ferromagnetic Ising model, and show how to efficiently use them on an arbitrary given graph to rigorously upper-bound the partition function, magnetizations, and correlations. The results…

Disordered Systems and Neural Networks · Physics 2017-05-24 Alaa Saade , Florent Krzakala , Lenka Zdeborová

The competition between spin glass ($SG$) and antiferromagnetic order ($AF$) is analyzed in two sublattice fermionic Ising models in the presence of a transverse $\Gamma$ and a parallel $H$ magnetic fields. The exchange interaction follows…

Strongly Correlated Electrons · Physics 2015-06-25 F. M. Zimmer , S. G. Magalhaes

We have studied the anisotropic three-dimensional nearest-neighbor Ising model with competitive interactions in an uniform longitudinal magnetic field $H$. The model consists of ferromagnetic interaction $J_{x}(J_{z})$ in the $x(z)$…

Statistical Mechanics · Physics 2012-06-29 Octavio D. R. Salmon , Minos A. Neto , J. Roberto Viana , Igor T. Padilha , J. R. de Sousa

A family of multispecies Ising models on generalized regular random graphs is investigated in the thermodynamic limit. The architecture is specified by class-dependent couplings and magnetic fields. We prove that the magnetizations,…

Mathematical Physics · Physics 2024-03-22 Diego Alberici , Pierluigi Contucci , Emanuele Mingione , Filippo Zimmaro

We study the magnetic properties of a mixed Ising ferrimagnetic system, in which the two interacting sublattices have spins $\sigma$, $(\pm 1/2)$ and spins $S$, $(\pm 3/2,\pm 1/2)$ in the presence of a random crystal field, with the mean…

Statistical Mechanics · Physics 2009-11-13 L. Bahmad , A. Benyoussef , A. El Kenz

An asymmetrical 2D Ising model with a zigzag surface, created by diagonally cutting a regular square lattice, has been developed to investigate the thermodynamics and phase transitions on surface by the methodology of recursive lattice,…

Statistical Mechanics · Physics 2019-01-31 Ran Huang , Purushottam D. Gujrati

Thermodynamic properties of the ferromagnetic Ising model on the hierarchical pentagon lattice is studied by means of the tensor network methods. The lattice consists of pentagons, where 3 or 4 of them meet at each vertex. Correlation…

Statistical Mechanics · Physics 2024-07-08 Takumi Oshima , Tomotoshi Nishino

We consider the random field Ising model and show rigorously that the spin glass susceptibility at equilibrium is always bounded by the ferromagnetic susceptibility, and therefore that no spin glass phase can be present at equilibrium out…

Disordered Systems and Neural Networks · Physics 2010-05-24 Florent Krzakala , Federico Ricci-Tersenghi , Lenka Zdeborová

We present a detailed study of the phase diagram of the Ising model in random graphs with arbitrary degree distribution. By using the replica method we compute exactly the value of the critical temperature and the associated critical…

Statistical Mechanics · Physics 2009-11-07 M. Leone , A. Vazquez , A. Vespignani , R. Zecchina

A mean-field model of Ising spin glass with the Hamiltonian being a sum of the infinite-range ferromagnetic and random antiferromagnetic interactions is studied. It is shown that this model has phase transition in external magnetic field…

Disordered Systems and Neural Networks · Physics 2007-05-23 P. N. Timonin

Understanding exotic forms of magnetism in quantum mechanical systems is a central goal of modern condensed matter physics, with implications from high temperature superconductors to spintronic devices. Simulating magnetic materials in the…

We discuss the finite-size scaling of the ferromagnetic Ising model on random regular graphs. These graphs are locally tree-like, and in the limit of large graphs, the Bethe approximation gives the exact free energy per site. In the…

Statistical Mechanics · Physics 2022-03-09 Suman Kulkarni , Deepak Dhar

We study the phase transition in a face-centered-cubic antiferromagnet with Ising spins as a function of the concentration $p$ of ferromagnetic bonds randomly introduced into the system. Such a model describes the spin-glass phase at strong…

Statistical Mechanics · Physics 2014-03-05 V. Thanh Ngo , D. Tien Hoang , Hung T. Diep , I. A. Campbell

We introduce a finite-connectivity ferromagnetic model with a three-spin interaction which has a crystalline (ferromagnetic) phase as well as a glass phase. The model is not frustrated, it has a ferromagnetic equilibrium phase at low…

Disordered Systems and Neural Networks · Physics 2009-11-07 S. Franz , M. Mezard , F. Ricci-Tersenghi , M. Weigt , R. Zecchina