Nunn Zachary R, Abert Claas, Suess Dieter, Girt Erol
Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada.
Faculty of Physics, University of Vienna, Austria.
Sci Adv. 2020 Nov 25;6(48). doi: 10.1126/sciadv.abd8861. Print 2020 Nov.
Interlayer exchange coupling in transition metal multilayers has been intensively studied for more than three decades and is incorporated into almost all spintronic devices. With the current spacer layers, only collinear magnetic alignment can be reliably achieved; however, controlling the coupling angle has the potential to markedly expand the use of interlayer exchange coupling. Here, we show that the coupling angle between the magnetic moments of two ferromagnetic layers can be precisely controlled by inserting a specially designed magnetic metallic spacer layer between them. The coupling angle is controlled solely by the composition of the spacer layer. Moreover, the biquadratic coupling strength, responsible for noncollinear alignment, is larger than that of current materials. These properties allow for the fabrication and study of not yet realized magnetic structures that have the potential to improve existing spintronic devices.
过渡金属多层膜中的层间交换耦合已经被深入研究了三十多年，并几乎被应用于所有的自旋电子器件中。使用当前的间隔层，只能可靠地实现共线磁排列；然而，控制耦合角有可能显著扩展层间交换耦合的应用范围。在这里，我们表明，通过在两个铁磁层之间插入一个特别设计的磁性金属间隔层，可以精确控制它们磁矩之间的耦合角。耦合角仅由间隔层的成分控制。此外，负责非共线排列的双二次耦合强度比现有材料的更大。这些特性使得制造和研究尚未实现的磁性结构成为可能，这些结构有可能改进现有的自旋电子器件。
