Search for a transition in the three-dimensional J Ising spin-glass

The three-dimensional Ising spin-glass in zero field with nearest-neighbor interactions having ±{}J distribution is studied by Monte Carlo simulations for samples of linear dimension L with 3{≤}L{≤}20. Results for the probability distribution, PL(q), of the spin-glass order parameter are analyzed by finite-size scaling. Data for T{≥}1.2 are consistent with a conventional phase transition at Tc{=1.2}_{{{-}}0.2}+0.1$, with exponents {ν}=1.3±{}0.3 and {η}=-0.3±{}0.2. However, results at lower temperature indicate marginal behavior and suggest that the lower critical dimensional is close to three.