Field-Shift Aging Protocol on the 3D Ising Spin-Glass Model: Dynamical Crossover between the Spin-Glass and Paramagnetic States

摘要

Spin-glass (SG) states of the 3-dimensional Ising Edwards-Anderson modelunder a static magnetic field $h$ are examined by means of the standard MonteCarlo simulation on the field-shift aging protocol at temperature $T$. For eachprocess with $(T; \tw, h)$, $\tw$ being the waiting time before the field isswitched on, we extract the dynamical crossover time, $\tcr(T; \tw, h)$. Wehave found a nice scaling relation between the two characteristic length scaleswhich are properly determined from $\tcr$ and $\tw$ and then are normalized bythe static field crossover length introduced in the SG droplet theory. Thisscaling behavior implies the instability of the SG phase in the equilibriumlimit even under an infinitesimal $h$. In comparison with this numerical resultthe field effect on real spin glasses is also discussed.