Dynamic Correlation Length Growth in Superspin Glass: Bridging   Experiments and Simulations
  Interacting magnetic nanoparticles display a wide variety of magnetic behaviors that are now being gathered in the emerging field of 'supermagnetism.' We have investigated how the out-of-equilibrium dynamics in the disordered superspin glass (SSG) state of a frozen ferrofluid sample is affected by texturation. Via magnetization relaxation experiments at low temperatures, we were able to estimate superspin correlation lengths for both textured and non-textured samples. The comparison with simulations and experiments on atomic spin glasses shows that the dynamic correlations in SSG's appear to develop in a way reminiscent to those in atomic spin glasses at intermediate time/length scales. 
Sawako Nakamae, Caroline Crauste-Thibierge, Denis L'Hote, Eric   Vincent, Emmanuelle Dubois, Vincent Dupuis and Regine Perzynski
cond-mat.dis-nn