Low-temperature behavior of two-dimensional Gaussian Ising spin glasses

We perform Monte Carlo simulations of large two-dimensional Gaussian Ising spin glasses down to very low temperatures β=1/T=50 . Equilibration is ensured by using a cluster algorithm including Monte Carlo moves consisting of flipping fundamental excitations. We study the thermodynamic behavior using the Binder cumulant, the spin-glass susceptibility, the distribution of overlaps, the overlap with the ground state, and the specific heat. We confirm that T_c=0 . All results are compatible with an algebraic divergence of the correlation length with an exponent ν . We find -1/ν=-0.295(40) , which is compatible with the value for the domain-wall and droplet exponent θ≈-0.29 found previously in ground-state studies. Hence the thermodynamic behavior of this model seems to be governed by one single exponent.