Finite-dimensional signature of spinodal instability in an athermal hysteretic transition

Article

关键词: MAGNETIC HYSTERESIS;    SCALING LAW;    NUCLEATION;    DISPERSION;    AVALANCHES;    DYNAMICS;    FILMS;    MODEL;    1ST;   

DOI  :  10.1103/PhysRevB.107.024103

来源: SCIE

【 摘 要 】

We study the off-equilibrium critical phenomena across a hysteretic first-order transition in disordered athermal systems. The study focuses on the zero temperature random field Ising model (ZTRFIM) above the critical disorder for spatial dimensions d = 2, 3, and 4. We use Monte Carlo simulations to show that disorder suppresses critical slowing down in phase ordering time for finite-dimensional systems. The dynamic hysteresis scaling, the measure of explicit finite-time scaling, is used to subsequently quantify the critical slowing down. The scaling exponents in all dimensions increase with disorder strength and finally reach a stable value where the transformation is no longer critical. The associated critical behavior in the mean-field limit is very different, where the exponent values for various disorders in all dimensions are similar. The non-mean-field exponents asymptotically approach the mean-field value (Gamma approximate to 2/3) with increase in dimensions. The results suggest that the critical features in the hysteretic metastable phase are controlled by inherent mean-field spinodal instability that gets blurred by disorder in low-dimension athermal systems.

【 授权许可】

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