2001/08/31 by Gilles Tarjus, Victor Dotsenko · 2 citations
Computer Science · Economics, Econometrics and Finance · Physics and Astronomy · #Complex Systems and Time Series Analysis #Theoretical and Computational Physics #Topological and Geometric Data Analysis #cond-mat.dis-nn
paper · pdf · doi:10.1088/0305-4470/35/7/311
29 pages
arxiv created 2001/12/18 · openalex publication_date 2002/02/11 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
In this paper we study the phase diagram of the disordered Ising ferromagnet. Within the framework of the Gaussian variational approximation it is shown that in systems with a finite value of the disorder in dimensions D = 4 and D < 4 the paramagnetic and ferromagnetic phases are separated by a spin-glass phase. The transition from paramagnetic to spin-glass state is continuous (second order), whereas the transition between spin-glass and ferromagnetic states is discontinuous (first order). It is also shown that within the considered approximation there is no replica symmetry breaking in the spin-glass phase. The validity of the Gaussian variational approximation for the present problem is discussed, and we provide a tentative physical interpretation of the results.