Spin-Valley Locking Effect in Defect States of Monolayer MoS2.
Spin-Valley Locking Effect in Defect States of Monolayer MoS2.
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DOI：
10.1021/acs.nanolett.0c00138
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发表时间：
2020-02
期刊：
影响因子：
10.8
通讯作者：
Yaqian Wang;L. Deng;Qilin Wei;Yilong Wan;Zhen Liu;X. Lu;Yue Li;L. Bi;Li Zhang;Haipeng Lu-H
中科院分区：
文献类型：
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作者：
Yaqian Wang;L. Deng;Qilin Wei;Yilong Wan;Zhen Liu;X. Lu;Yue Li;L. Bi;Li Zhang;Haipeng Lu-H
二维过渡金属二硫属化物（TMD）中的谷赝自旋可以实现自旋谷极化和谷间量子相干的光学控制。TMD中的缺陷态会产生新的激子特征，理论上表现出自旋谷极化，然而，这种现象的实验实现仍然存在挑战。在这里，我们报告明确的谷赝自旋的缺陷束缚局域激子在CVD生长的单层二硫化钼增强谷塞曼分裂的有效g因子为-6.2。我们的研究结果表明，所有五个d轨道和增加的有效电子质量有助于缺陷态的带移，展示了一个新的物理缺陷束缚局域激子的磁响应，显着不同的A激子。我们的工作铺平了道路的自旋谷自由度的操纵，通过对valleytronic设备的缺陷。
Valley pseudospin in two-dimensional (2D) transition-metal dichalcogenides (TMDs) allows optical control of spin-valley polarization and intervalley quantum coherence. Defect states in TMDs give rise to new exciton features and theoretically exhibit spin-valley polarization; however, experimental achievement of this phenomenon remains challenges. Here, we report unambiguous valley pseudospin of defect-bound localized excitons in CVD-grown monolayer MoS2; enhanced valley Zeeman splitting with an effective g-factor of -6.2 is observed. Our results reveal that all five d-orbitals and the increased effective electron mass contribute to the band shift of defect states, demonstrating a new physics of the magnetic responses of defect-bound localized excitons, strikingly different from that of A excitons. Our work paves the way for the manipulation of the spin-valley degrees of freedom through defects toward valleytronic devices.