论文标题
用持续的自旋纹理旋转分裂，由单层单相过渡金属二核苷的线缺陷引起的旋转纹理
Spin splitting with persistent spin textures induced by the line defect in 1T-phase of monolayer transition metal dichalcogenides
论文作者
论文摘要
由单层（ML）过渡金属二分法（TMDCS）家族驱动的自旋分裂仅针对1H相结构进行了广泛的研究，而由于晶体的中心对称性而言，它并不是1T阶段结构。基于第一原理计算，我们表明可以通过引入线路缺陷在ML 1T-TMDC中诱导显着的自旋分裂。以ML PTSE2为代表性的例子，我们考虑了线路缺陷的最稳定形式，即Se-Se-Vacancy Line缺陷（SE-VLD）。我们发现在SE-VLD的缺陷状态下观察到大型自旋分裂，在动量空间中表现出高度单向的自旋构型。这种奇特的自旋构型可能会产生所谓的持续自旋纹理（PST），这是一种特定的自旋结构，可防止自旋脱发并支持非常长的自旋寿命。此外，通过使用补充对称分析的K.P扰动理论，我们澄清说，旋转分裂的出现保持缺陷状态中的PST源于倒置对称性的破坏，以及SE-VLD工程ML PTSE2的一维性质。我们的发现铺平了一种诱导ML 1T-TMDC中显着自旋分裂的可能方法，这对于设计自旋设备非常重要。
The spin splitting driven by spin-orbit coupling in monolayer (ML) transition metal dichalcogenides (TMDCs) family has been widely studied only for the 1H-phase structure, while it is not profound for the 1T-phase structure due to the centrosymmetric of the crystal. Based on first-principles calculations, we show that significant spin splitting can be induced in the ML 1T-TMDCs by introducing the line defect. Taking the ML PtSe2 as a representative example, we considered the most stable form of the line defects, namely Se-vacancy line defect (Se-VLD). We find that large spin splitting is observed in the defect states of the Se-VLD, exhibiting a highly unidirectional spin configuration in the momentum space. This peculiar spin configuration may yield the so-called persistent spin textures (PST), a specific spin structure resulting in protection against spin-decoherence and supporting an extraordinarily long spin lifetime. Moreover, by using k.p perturbation theory supplemented with symmetry analysis, we clarified that the emerging of the spin splitting maintaining the PST in the defect states is originated from the inversion symmetry breaking together with one-dimensional nature of the Se-VLD engineered ML PtSe2. Our findings pave a possible way to induce the significant spin splitting in the ML 1T-TMDCs, which could be highly important for designing spintronic devices.
