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Numerical Study of Competing Spin-Glass and Ferromagnetic Order

M. V. Simkin
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Abstract

Two and three dimensional random Ising models with a Gaussian distribution of couplings with variance $J$ and non-vanishing mean value $J_0$ are studied using the zero-temperature domain-wall renormalization group (DWRG). The DWRG trajectories in the ($J_0,J$) plane after rescaling can be collapsed on two curves: one for $J_0/J > r_c$ and other for $J_0/J < r_c$. In the first case the DWRG flows are toward the ferromagnetic fixed point both in two and three dimensions while in the second case flows are towards a paramagnetic fixed point and spin-glass fixed point in two and three dimensions respectively. No evidence for an extra phase is found.

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M. V. Simkin. 1997-01-09. Numerical Study of Competing Spin-Glass and Ferromagnetic Order. https://doi.org/10.1103/physrevb.55.11405

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