Effect of the thermal quench on aging in spin glasses

We probe the effects of different initial conditions on the process of aging in spin glasses arising from alternative temperature quenching protocols for the canonical and representative Cu:Mn (6 at.%) dilute magnetic alloy. The effects of these changes are observed through the decay of the thermoremanent magnetization, M-TRM(t). We find significant changes in the initial state as a consequence of the different cooling processes, reflected through an effective waiting time, t(w)(eff). The effective waiting time shortens as the time spent above the measuring temperature in the cooling protocol is reduced, reaching a minimum when the temperature is not allowed to rise above the final measurement temperature after the initial quench. This behavior is consistent with the picture of a rapid temperature dependence of the barrier heights separating metastable states.