Barkhausen noise in disordered ferromagnets is typically understood to originate primarily from jerky field-driven motion of domain walls. We study the magnetization reversal process in disordered permalloy thin films using micromagnetic simulations, and find that the magnetization reversal process consists of the gradual formation of immobile 360$^{\circ}$ domain walls via a sequence of localized magnetization rotation events. The density of 360$^{\circ}$ domain walls formed within the sample as well as the statistical properties of the Barkhausen jumps are controlled by the disorder strength.

中文翻译：

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无序坡莫合金薄膜中 360$^{\circ}$ 畴壁形成的巴克豪森噪声

无序铁磁体中的巴克豪森噪声通常被理解为主要源自畴壁的急速场驱动运动。我们使用微磁模拟研究了无序坡莫合金薄膜中的磁化反转过程，发现磁化反转过程包括通过一系列局部磁化旋转事件逐渐形成固定的 360$^{\circ}$ 畴壁。样本内形成的 360$^{\circ}$ 畴壁的密度以及巴克豪森跃迁的统计特性由无序强度控制。