Dynamics in spin glasses

摘要: Below the freezing temperature ${\mathit{T}}_{\mathit{g}}$, configuration space of spin glasses is characterized by existence quasidegenerate equilibrium states whose number increases drastically as lowered. The observed time dependence dynamical properties (aging effects) can be understood trend system towards thermal between all accessible states. We present a series cycling experiments on decay remanent magnetization in Ag:Mn(2.6 at. %). results are consistent with picture an ultrametric organization metastable states, predicted Parisi solution Sherrington-Kirkpatrick model. Within this interpretation, height barrier two determined experimentally. also establish quantitative relationship ${\mathrm{\ensuremath{\Delta}}}_{\mathrm{\ensuremath{\alpha}}\mathrm{\ensuremath{\beta}}}$ and Hamming distance ${\mathit{d}}_{\mathrm{\ensuremath{\alpha}}\mathrm{\ensuremath{\beta}}}$ separating \ensuremath{\alpha} \ensuremath{\beta}. This experimental result compared numerical simulations mean-field glasses.