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Short Range Ising Spin Glasses: a critical exponent study

E. Nogueira Jr.·S. Coutinho·F. D. Nobre·E. M. F. Curado
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Abstract

The critical properties of short-range Ising spin-glass models, defined on a diamond hierarchical lattice of graph fractal dimension $d_{f}=2.58$, 3, and 4, and scaling factor 2 are studied via a method based on the Migdal-Kadanoff renormalization-group scheme. The order parameter critical exponent $β$ is directly estimated from the data of the local Edwards- Anderson (EA) order parameter, obtained through an exact recursion procedure. The scaling of the EA order parameter, leading to estimates of the $ν$ exponent of the correlation length is also performed. Four distinct initial distributions of the quenched coupling constants (Gaussian, bimodal, uniform and exponential) are considered. Deviations from a universal behaviour are observed and analysed in the framework of the renormalized flow in a two dimensional appropriate parameter space.

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E. Nogueira Jr., S. Coutinho, F. D. Nobre, E. M. F. Curado. 1998-09-20. Short Range Ising Spin Glasses: a critical exponent study. https://doi.org/10.1016/s0378-4371(98)00160-5

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