Sethi P, Murapaka C, Goolaup S, Chen Y J, Leong S H, Lew W S
School of Physical &Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371.
Data Storage Institute, (A*STAR) Agency for Science, Technology and Research, DSI Building, 5 Engineering Drive 1, Singapore 117608.
Sci Rep. 2016 Jan 12;6:19027. doi: 10.1038/srep19027.
Controlling the domain wall (DW) trajectory in magnetic network structures is crucial for spin-based device related applications. The understanding of DW dynamics in network structures is also important for study of fundamental properties like observation of magnetic monopoles at room temperature in artificial spin ice lattice. The trajectory of DW in magnetic network structures has been shown to be chirality dependent. However, the DW chirality periodically oscillates as it propagates a distance longer than its fidelity length due to Walker breakdown phenomenon. This leads to a stochastic behavior in the DW propagation through the network structure. In this study, we show that the DW trajectory can be deterministically controlled in the magnetic network structures irrespective of its chirality by introducing a potential barrier. The DW propagation in the network structure is governed by the geometrically induced potential barrier and pinning strength against the propagation. This technique can be extended for controlling the trajectory of magnetic charge carriers in an artificial spin ice lattice.
控制磁网络结构中的畴壁（DW）轨迹对于基于自旋的器件相关应用至关重要。理解网络结构中的DW动力学对于研究诸如在人造自旋冰晶格中室温下观察磁单极子等基本性质也很重要。磁网络结构中DW的轨迹已被证明与手性有关。然而，由于沃克击穿现象，DW手性在传播超过其保真长度的距离时会周期性振荡。这导致DW在通过网络结构传播时出现随机行为。在本研究中，我们表明，通过引入势垒，无论其手性如何，都可以在磁网络结构中确定性地控制DW轨迹。网络结构中DW的传播由几何诱导势垒和对传播的钉扎强度控制。该技术可扩展用于控制人造自旋冰晶格中磁电荷载流子的轨迹。
