论文标题
2D无序的Ising模型中的有限温度雪崩
Finite-temperature avalanches in 2D disordered Ising models
论文作者
论文摘要
我们研究了随机温度下在有限温度下出现的Barkhausen噪声的定性和定量特性。使用Wolff群集蒙特卡洛算法研究随机键模模型，以监视外部驾驶磁场产生的雪崩。发现令人满意的幂律分布会在五十年内扩展，其中与温度有关的临界指数与现有的实验测量相匹配。我们还专注于一个Ising系统，其中有限的缺陷部分被淬灭。同样，缺陷的存在证明能够引起对缓慢振荡磁场的关键反应，尽管在这种情况下，与与不同缺陷分数和温度所获得的分布相关的关键指数似乎属于同一普遍性类别，其关键指数等于1。
We study the qualitative and quantitative properties of the Barkhausen noise emerging at finite temperatures in random Ising models. The random-bond Ising Model is studied with a Wolff cluster Monte-Carlo algorithm to monitor the avalanches generated by an external driving magnetic field. Satisfactory power-law distributions are found which expand over five decades, with a temperature-dependent critical exponent which matches the existing experimental measurements. We also focus on a Ising system in which a finite fraction of defects is quenched. Also the presence of defects proves able to induce a critical response to a slowly oscillating magnetic field, though in this case the critical exponent associated with the distributions obtained with different defect fractions and temperatures seems to belong to the same universality class, with a critical exponent equal to 1.
