Huang Mantao, Hasan Muhammad Usama, Klyukin Konstantin, Zhang Delin, Lyu Deyuan, Gargiani Pierluigi, Valvidares Manuel, Sheffels Sara, Churikova Alexandra, Büttner Felix, Zehner Jonas, Caretta Lucas, Lee Ki-Young, Chang Joonyeon, Wang Jian-Ping, Leistner Karin, Yildiz Bilge, Beach Geoffrey S D
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, USA.
Nat Nanotechnol. 2021 Sep;16(9):981-988. doi: 10.1038/s41565-021-00940-1. Epub 2021 Jul 29.
Voltage control of magnetic order is desirable for spintronic device applications, but 180° magnetization switching is not straightforward because electric fields do not break time-reversal symmetry. Ferrimagnets are promising candidates for 180° switching owing to a multi-sublattice configuration with opposing magnetic moments of different magnitudes. In this study we used solid-state hydrogen gating to control the ferrimagnetic order in rare earth-transition metal thin films dynamically. Electric field-induced hydrogen loading/unloading in GdCo can shift the magnetic compensation temperature by more than 100 K, which enables control of the dominant magnetic sublattice. X-ray magnetic circular dichroism measurements and ab initio calculations indicate that the magnetization control originates from the weakening of antiferromagnetic exchange coupling that reduces the magnetization of Gd more than that of Co upon hydrogenation. We observed reversible, gate voltage-induced net magnetization switching and full 180° Néel vector reversal in the absence of external magnetic fields. Furthermore, we generated ferrimagnetic spin textures, such as chiral domain walls and skyrmions, in racetrack devices through hydrogen gating. With gating times as short as 50 μs and endurance of more than 10,000 cycles, our method provides a powerful means to tune ferrimagnetic spin textures and dynamics, with broad applicability in the rapidly emerging field of ferrimagnetic spintronics.
对于自旋电子器件应用而言，磁序的电压控制是很有必要的，但180°磁化翻转并非易事，因为电场不会破坏时间反演对称性。由于具有不同大小相反磁矩的多亚晶格结构，亚铁磁体是实现180°翻转的有前景的候选材料。在本研究中，我们使用固态氢门控来动态控制稀土-过渡金属薄膜中的亚铁磁序。电场诱导的GdCo中的氢加载/卸载可使磁补偿温度偏移超过100 K，这使得能够控制占主导地位的磁性亚晶格。X射线磁圆二色性测量和从头算计算表明，磁化控制源于反铁磁交换耦合的减弱，氢化时这种减弱对Gd磁化的降低比对Co磁化的降低更多。我们在没有外部磁场的情况下观察到了可逆的、栅极电压诱导的净磁化翻转和完全180°的奈尔矢量反转。此外，我们通过氢门控在跑道型器件中产生了亚铁磁自旋纹理，如手性畴壁和斯格明子。我们的方法具有50 μs的短门控时间和超过10000次循环的耐久性，为调节亚铁磁自旋纹理和动力学提供了一种强大手段，在迅速兴起的亚铁磁自旋电子学领域具有广泛的适用性。
