Filippou Panagiotis Ch, Faleev Sergey V, Garg Chirag, Jeong Jaewoo, Ferrante Yari, Topuria Teya, Samant Mahesh G, Parkin Stuart S P
IBM Research-Almaden, San Jose, CA 95120, USA.
Samsung Semiconductor Inc., San Jose, CA 95134, USA.
Sci Adv. 2022 Feb 25;8(8):eabg2469. doi: 10.1126/sciadv.abg2469. Epub 2022 Feb 23.
Antiferromagnet spintronic devices eliminate or mitigate long-range dipolar fields, thereby promising ultrafast operation. For spin transport electronics, one of the most successful strategies is the creation of metallic synthetic antiferromagnets, which, to date, have largely been formed from transition metals and their alloys. Here, we show that synthetic antiferrimagnetic sandwiches can be formed using exchange coupling spacer layers composed of atomically ordered RuAl layers and ultrathin, perpendicularly magnetized, tetragonal ferrimagnetic Heusler layers. Chemically ordered RuAl layers can both be grown on top of a Heusler layer and allow for the growth of ordered Heusler layers deposited on top of it that are as thin as one unit cell. The RuAl spacer layer gives rise to a thickness-dependent oscillatory interlayer coupling with an oscillation period of ~1.1 nm. The observation of ultrathin ordered synthetic antiferrimagnets substantially expands the family of synthetic antiferromagnets and magnetic compounds for spintronic technologies.
反铁磁自旋电子器件可消除或减轻长程偶极场，因此有望实现超快运行。对于自旋输运电子学而言，最成功的策略之一是制造金属合成反铁磁体，迄今为止，这些反铁磁体主要由过渡金属及其合金构成。在此，我们表明，可使用由原子有序的RuAl层和超薄、垂直磁化的四方亚铁磁赫斯勒层组成的交换耦合间隔层来形成合成反铁磁夹层。化学有序的RuAl层既可以生长在赫斯勒层之上，也能使沉积在其上面的有序赫斯勒层生长得薄至一个晶胞。RuAl间隔层会产生厚度依赖的振荡层间耦合，振荡周期约为1.1纳米。超薄有序合成反铁磁体的发现极大地扩展了用于自旋电子技术的合成反铁磁体和磁性化合物家族。
