Van der Waals heterostructures offer attractive opportunities to design quantum materials. For instance, transition metal dichalcogenides (TMDs) possess three quantum degrees of freedom: spin, valley index, and layer index. Further, twisted TMD heterobilayers can form moir\'e patterns that modulate the electronic band structure according to atomic registry, leading to spatial confinement of interlayer exciton (IXs). Here we report the observation of spin-layer locking of IXs trapped in moir\'e potentials formed in a heterostructure of bilayer 2H-MoSe2 and monolayer WSe2. The phenomenon of locked electron spin and layer index leads to two quantum-confined IX species with distinct spin-layer-valley configurations. Furthermore, we observe that the atomic registries of the moir\'e trapping sites in the three layers are intrinsically locked together due to the 2H-type stacking characteristic of bilayer TMDs. These results identify the layer index as a useful degree of freedom to engineer tunable few-level quantum systems in two-dimensional heterostructures.
@article{arxiv.1908.03778,
title = {Spin-layer locking of interlayer excitons trapped in moir\'e potentials},
author = {Mauro Brotons-Gisbert and Hyeonjun Baek and Alejandro Molina-Sánchez and Aidan Campbell and Eleanor Scerri and Daniel White and Kenji Watanabe and Takashi Taniguchi and Cristian Bonato and Brian D. Gerardot},
journal= {arXiv preprint arXiv:1908.03778},
year = {2020}
}
Comments
10 pages, 4 figures. Supplementary Material available at: https://www.dropbox.com/s/8331cfoasdofwkq/Brotons-Gisbert_Suppl_Info.pdf?dl=0