论文标题
可调旋转和轨道Edelstein效果(111)Laalo $ _3 $/srtio $ _3 $接口
Tunable spin and orbital Edelstein effect at (111) LaAlO$_3$/SrTiO$_3$ interface
论文作者
论文摘要
将电荷电流转换为自旋电流是旋转基质中利用的主要机制之一。一个突出的例子是爱德尔斯坦效应,即响应外部电场的磁化产生,这可以在缺乏反转对称性的系统中实现。如果系统具有具有轨道角动量特征的电子,则可以通过施加的电场产生轨道磁化,从而产生所谓的轨道Edelstein效应。氧化物异质结构是由于强旋转轨道耦合和缺乏反转对称性而导致的这些效果的理想平台。除了栅极可调的旋转Edelstein效应之外,我们还预测轨道Edelstein效应的效果比(111)Laalo $ _3 $/srtio $ _3 $接口处的旋转效果大。我们使用紧密结合方法将材料建模为$ t_ {2g} $轨道的双层,而在Boltzmann方法中则获得了传输属性。我们在低填充下提供了一个有效的模型,该模型解释了Edelstein响应的非平凡行为,表明电子带之间的杂交对Edelstein的敏感性产生了至关重要的影响。
Converting charge current into spin current is one of the main mechanisms exploited in spintronics. One prominent example is the Edelstein effect, namely the generation of a magnetization in response to an external electric field, which can be realized in systems with lack of inversion symmetry. If a system has electrons with an orbital angular momentum character, an orbital magnetization can be generated by the applied electric field giving rise to the so-called orbital Edelstein effect. Oxide heterostructures are the ideal platform for these effects due to the strong spin-orbit coupling and the lack of inversion symmetries. Beyond a gate-tunable spin Edelstein effect, we predict an orbital Edelstein effect an order of magnitude larger then the spin one at the (111) LaAlO$_3$/SrTiO$_3$ interface. We model the material as a bilayer of $t_{2g}$ orbitals using a tight-binding approach, while transport properties are obtained in the Boltzmann approach. We give an effective model at low filling which explains the non-trivial behaviour of the Edelstein response, showing that the hybridization between the electronic bands crucially impacts the Edelstein susceptibility.