Computational experiment on glassy dynamic nature of field-cooled magnetization in Ising spin-glass model

The field-cooled (FC) process on an Ising spin-glass model is investigated by a standard Monte Carlo (MC) method, and the equilibrium magnetization of the same system is evaluated by the exchange MC method. The two types of simulation reveal intriguing glassy (nonequilibrium) dynamic properties of the FC magnetization (FCM) of the system. In particular, the FCM decrease is observed when the FC process is halted at a low temperature, although its value is smaller than the corresponding equilibrium value. We present a comprehensive interpretation of such peculiar phenomena on the basis of the scenario for the FCM process recently proposed by Jonsson and one of us (HT).