论文标题
部分可观测时空混沌系统的无模型预测
Self organized criticality of magnetic avalanches in disordered ferrimagnetic material
论文作者
论文摘要
我们在2 K处的磁性磁滞曲线中观察到在基于Dy-Fe-GA的铁磁合金中有多个阶梯状的跳跃。观察到的跳跃相对于它们的幅度和发生的临界场具有随机特征，并且跳跃没有显示任何时间效应。跳跃尺寸分布遵循功率定律变化，表明跳跃的规模不变性。我们调用了一个简单的二维随机键ising型自旋系统来对动力学进行建模。我们的计算工作可以定性地再现跳高及其规模不变特征。它还阐明了抗磁性耦合的Dy和Fe簇的翻转负责磁滞回路中观察到的类似雪崩的特征。这些特征表明，本现象可以在自组织临界的领域中得到很好的描述
We observe multiple step-like jumps in a Dy-Fe-Ga-based ferrimagnetic alloy in its magnetic hysteresis curve at 2 K. The observed jumps have a stochastic character with respect to their magnitude and the critical field of occurrence, and the jumps do not show any temporal effect. The jump size distribution follows a power law variation indicating the scale invariance nature of the jumps. We have invoked a simple two-dimensional random bond Ising-type spin system to model the dynamics. Our computational work can qualitatively reproduce the jumps and their scale invariant character. It also elucidates that the flipping of antiferromagnetically coupled Dy and Fe clusters is responsible for the observed discrete avalanche-like features in the hysteresis loop. These characteristics indicate that the present phenomenon can be well described within the realm of self-organized criticality
