Multioverlap Simulations of the 3D Edwards-Anderson Ising Spin Glass

We introduce a novel method for numerical spin glass investigations: Simulations of two replica at fixed temperature, weighted to achieve a broad distribution of the Parisi overlap parameter $q$ (multioverlap). We demonstrate the feasibility of the approach by studying the 3D Edwards-Anderson Ising ( $J_{\mathrm{ik}}=\pm 1$) spin glass in the broken phase ( $\beta =1\mathrm{}$). This makes it possible to obtain reliable results about spin glass tunneling barriers. In addition, our results indicate a nontrivial scaling behavior of the canonical $q$ distributions not only at the freezing point but also deep in the broken phase.