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Universality in short-range Ising spin glasses

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

The role of the distribution of coupling constants on the critical exponents of the short-range Ising spin-glass model is investigated via real space renormalization group. A saddle-point spin glass critical point characterized by a fixed-point distribution is found in an appropriated parameter space. The critical exponents $β$ and $ν$ are directly estimated from the data of the local Edwards-Anderson order parameters for the model defined on a diamond hierarchical lattice of fractal dimension $d_{f}=3$. Four distinct initial distributions of coupling constants (Gaussian, bimodal, uniform and exponential) are considered; the results clearly indicate a universal behavior.

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E. Nogueira Jr., S. Coutinho, F. D. Nobre, E. M. F. Curado. 1999-06-08. Universality in short-range Ising spin glasses. https://doi.org/10.1016/s0378-4371(99)00229-0

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