As the first magnetic random access memories are finding their way onto the market, an important issue remains to be solved: the current density required to write magnetic bits becomes prohibitively high as bit dimensions are reduced. Recently, spin–orbit torques and the spin-Hall effect in particular have attracted significant interest, as they enable magnetization reversal without high current densities running through the tunnel barrier. For perpendicularly magnetized layers, however, the technological implementation of the spin-Hall effect is hampered by the necessity of an in-plane magnetic field for deterministic switching. Here we interface a thin ferromagnetic layer with an anti-ferromagnetic material. An in-plane exchange bias is created and shown to enable field-free S HE-driven magnetization reversal of a perpendicularly magnetized Pt/Co/IrMn structure. Aside from the potential technological implications, our experiment provides additional insight into the local spin structure at the ferromagnetic/anti-ferromagnetic interface.
展开▼
机译:随着第一批磁性随机存取存储器进入市场,还有一个重要的问题有待解决:随着位尺寸的减小,写入磁性位所需的电流密度变得过高。最近,自旋轨道转矩特别是自旋霍尔效应引起了人们极大的兴趣,因为它们可以使磁化反转而无需高电流密度穿过隧道势垒。然而,对于垂直磁化的层,自旋霍尔效应的技术实现受到用于确定性切换的平面内磁场的必要性的阻碍。在这里,我们将薄铁磁层与反铁磁材料相接。创建并显示了一个面内交换偏压,以实现垂直磁化的Pt / Co / IrMn结构的无场S HE驱动的磁化反转。除了潜在的技术含义外,我们的实验还提供了对铁磁/反铁磁界面处的局部自旋结构的进一步了解。
展开▼