Ferromagnetic-spin glass transition in four-dimensional random-bond Ising model

Alexander K. Hartmann

doi:10.1103/physrevb.64.224430

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Ferromagnetic-spin glass transition in four-dimensional random-bond Ising model

Alexander K. Hartmann

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Abstract

The four-dimensional +-J random-bond Ising model is studied using ground-state calculations. System sizes up to N=6^4 spins are considered. Here it is found that the ferromagnetic-spin glass transition occurs at a critical concentration p_c=0.28(1) of the antiferromagnetic bonds, which is comparable to values found previously by high-temperature series expansions. The transition is characterized by a correlation-length exponent ν=1.0(1) and an order-parameter exponent β=0.4(1). Thus, this transition is in a different universality class from four-dimensional bond percolation, where ν=0.678(50) and β=0.639(20).

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Alexander K. Hartmann. 2001-07-28. Ferromagnetic-spin glass transition in four-dimensional random-bond Ising model. https://doi.org/10.1103/physrevb.64.224430

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