Evidence for a Finite-Temperature Spin Glass Transition in a Diluted Dipolar Heisenberg Model in Three Dimensions

Abstract

By means of parallel tempering Monte Carlo simulations we find strong evidence for a finite-temperature spin-glass transition in a system of diluted classical Heisenberg dipoles randomly placed on the sites of a simple cubic lattice. We perform a finite-size scaling analysis of the spin-glass susceptibility, ${\chi }_{\mathrm{SG}}$, and spin-glass correlation length, ${\xi }_L$. For the available system sizes that can be successfully equilibrated, the crossing of ${\xi }_L/L$ versus temperature is strongly affected by corrections to scaling and possibly by a short-length scale ferromagnetic spin blocking. Similarly to many studies of different three dimensional spin-glass systems, we do not find a crossing of the spin glass order parameter Binder ratio.

17 pages, 15 figures. Submitted to Physical Review B