Department of Applied Physics and Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, 94305, USA.
CEMES, University of Toulouse, CNRS, UPS, 29, rue Jeanne Marvig, 31055, Toulouse, France.
Nat Commun. 2018 Apr 13;9(1):1458. doi: 10.1038/s41467-018-04014-0.
The manipulation of the spin degrees of freedom in a solid has been of fundamental and technological interest recently for developing high-speed, low-power computational devices. There has been much work focused on developing highly spin-polarized materials and understanding their behavior when incorporated into so-called spintronic devices. These devices usually require spin splitting with magnetic fields. However, there is another promising strategy to achieve spin splitting using spatial symmetry breaking without the use of a magnetic field, known as Rashba-type splitting. Here we report evidence for a giant Rashba-type splitting at the interface of LaTiO and SrTiO. Analysis of the magnetotransport reveals anisotropic magnetoresistance, weak anti-localization and quantum oscillation behavior consistent with a large Rashba-type splitting. It is surprising to find a large Rashba-type splitting in 3d transition metal oxide-based systems such as the LaTiO/SrTiO interface, but it is promising for the development of a new kind of oxide-based spintronics.
最近，人们对固体中自旋自由度的操纵产生了浓厚的兴趣，因为这对于开发高速、低功耗的计算设备具有重要的基础和技术意义。人们已经做了大量的工作来开发具有高自旋极化率的材料，并研究它们在所谓的自旋电子器件中的行为。这些器件通常需要通过磁场来实现自旋分裂。然而，还有另一种很有前途的策略可以在不使用磁场的情况下利用空间对称破缺来实现自旋分裂，这种方法被称为 Rashba 型分裂。在这里，我们报告了在 LaTiO 和 SrTiO 的界面处存在巨大的 Rashba 型分裂的证据。磁输运分析表明，各向异性磁电阻、弱反局域和量子振荡行为与较大的 Rashba 型分裂一致。在 LaTiO/SrTiO 界面等 3d 过渡金属氧化物基系统中发现大的 Rashba 型分裂是令人惊讶的，但这为开发新型的氧化物基自旋电子学提供了希望。
