Interplay between aging and rejuvenation in spin glasses

Aging in a single-crystal spin glass (Cu0.92Mn0.08) has been measured using ac susceptibility techniques over a temperature range of 0.3–0.8 Tg. In these studies, traditional aging experiments (or “quench” aging protocols) are compared to aging curves constructed from finite-cooling-rate curves. By comparing the growth rates of spin glass order between the two types of aging curves, it is determined that quantitative comparisons between protocols that are taken by quenching and protocols using a finite cooling rate are not possible without a deeper understanding of the interplay between aging and rejuvenation. We then demonstrate that the data presented indicate that rejuvenation, rather than cumulative aging, is the cause of the discrepancies between the two growth rates.