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Related papers: Fermionic Quantum Spin Glass Transitions

200 papers

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

Models with range-free frustrated Ising spin- and Hubbard interaction are treated exactly by means of the discrete time slicing method. Critical and tricritical points, correlations, and the fermion propagator, are derived as a function of…

Disordered Systems and Neural Networks · Physics 2009-11-07 R. Oppermann , D. Sherrington

We have examined the role of the BCS pairing mechanism in the formation of the magnetic moment and henceforth a spin glass (SG) phase by studying a fermionic Sherrington-Kirkpatrick model with a local BCS coupling between the fermions. This…

Statistical Mechanics · Physics 2016-08-31 S. G. Magalhaes , Alba Theumann

Distinctive orderings and phase diagram structures are found, from renormalization-group theory, for odd q-state clock spin-glass models in d=3 dimensions. These models exhibit asymmetric phase diagrams, as is also the case for quantum…

Statistical Mechanics · Physics 2015-03-04 Efe Ilker , A. Nihat Berker

We study the Coulomb glass emerging from the interplay of strong interactions and disorder in a model of spinless fermions on the Bethe lattice. In the infinite coordination number limit, strong interactions induce a metallic Coulomb glass…

Disordered Systems and Neural Networks · Physics 2025-04-08 Izabella Lovas , Annamária Kiss , Cătălin Paşcu Moca , Gergely Zaránd

Quantum annealers are commercial devices aiming to solve very hard computational problems named spin glasses. Just like in metallurgic annealing one slowly cools a ferrous metal, quantum annealers seek good solutions by slowly removing the…

Disordered Systems and Neural Networks · Physics 2025-01-22 Massimo Bernaschi , Isidoro González-Adalid Pemartín , Víctor Martín-Mayor , Giorgio Parisi

We report some results on the quenched disordered Spherical multi-$p$-Spin Model in presence of ferromagnetic couplings. In particular, we present the phase diagrams of some representative cases that schematically describe, in the…

Disordered Systems and Neural Networks · Physics 2013-03-19 Andrea Crisanti , Luca Leuzzi

An analytical approach, which develops the gauge model of the glass transition phenomenon, is suggested. It is based on the quantum field theory and critical dynamics methods. The suggested mechanism of glass transition is based on the…

Statistical Mechanics · Physics 2011-05-12 Mikhail Vasin

We study a quantum extension of the spherical $p$-spin-glass model using the imaginary-time replica formalism. We solve the model numerically and we discuss two analytical approximation schemes that capture most of the features of the…

Disordered Systems and Neural Networks · Physics 2009-10-31 Leticia F Cugliandolo , D. R. Grempel , Constantino A da Silva Santos

We perform numerical simulations, including parallel tempering, on the Potts glass model with binary random quenched couplings using the JANUS application-oriented computer. We find and characterize a glassy transition, estimating the…

The ferromagnetic phase of an Ising model in d=3, with any amount of quenched antiferromagnetic bond randomness, is shown to undergo a transition to a spin-glass phase under sufficient quenched bond dilution. This general result,…

Disordered Systems and Neural Networks · Physics 2009-03-30 Gül Gülpınar , A. Nihat Berker

The interplay of spin and charge fluctuations in the random transverse-field Ising spin chain on the fermionic space is investigated. The finite chemical potential, which controls the charge fluctuations, leads to the appearance of the…

Disordered Systems and Neural Networks · Physics 2009-10-31 A. L. Chudnovskiy

We report progress in understanding the fermionic Ising spin glass with arbitrary filling. A crossover from a magnetically disordered single band phase via two intermediate bands just below the freezing temperature to a 3-band structure at…

Strongly Correlated Electrons · Physics 2007-05-23 R. Oppermann , H. Feldmann

We consider the thermodynamics of an infinite-range Ising p-spin glass model with an additional r-spin ferromagnetic interaction. For r=2 there is a continuous transition to a ferromagnetic phase, while for r>2 the transition is first…

Disordered Systems and Neural Networks · Physics 2009-11-07 Peter Gillin , Hidetoshi Nishimori , David Sherrington

We consider a gauge theory of the glass transition in the frustrated XY model being simplest model containing topologically nontrivial excitations. We describe the transition kinetics and find that the three-dimensional system exhibits the…

Statistical Mechanics · Physics 2019-06-26 Mikhail Vasin

In this talk I review some recent developments which shed light on the main connections between structural glasses and mean-field spin glass models with a discontinuous transition. I also discuss the role of quantum fluctuations on the…

Disordered Systems and Neural Networks · Physics 2009-10-28 Felix Ritort

We study a fermionic infinited-ranged Ising spin glass with a real space BCS interaction in the presence of an applied transverse field. The problem is formulated in the integral functional formalism where the SU(2) spins are given in terms…

Superconductivity · Physics 2009-11-10 S. G Magalhães , F. M. Zimmer

The quantum critical behavior of the Ising glass in a magnetic field is investigated. We focus on the spin glass to paramagnet transition of the transverse degrees of freedom in the presence of finite longitudinal field. We use two…

Strongly Correlated Electrons · Physics 2009-11-10 L. Arrachea , D. Dalidovich , V. Dobrosavljević , M. J. Rozenberg

Continuous phase transitions are catalogued into universality classes, families of systems having identical values of all the exponents governing the critical behaviour of their different physical properties. Numerical simulations have been…

Disordered Systems and Neural Networks · Physics 2007-05-23 P. O. Mari , I. A. Campbell

Employing the self-learning quantum Monte Carlo algorithm, we investigate the frustrated transverse-field triangle-lattice Ising model coupled to a Fermi surface. Without fermions, the spin degrees of freedom undergoes a second-order…

Strongly Correlated Electrons · Physics 2018-07-17 Zi Hong Liu , Xiao Yan Xu , Yang Qi , Kai Sun , Zi Yang Meng