We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Quadrupolar excitons and hybridized interlayer Mott insulator in a trilayer moiré superlattice.
- Authors
Lian, Zhen; Chen, Dongxue; Ma, Lei; Meng, Yuze; Su, Ying; Yan, Li; Huang, Xiong; Wu, Qiran; Chen, Xinyue; Blei, Mark; Taniguchi, Takashi; Watanabe, Kenji; Tongay, Sefaattin; Zhang, Chuanwei; Cui, Yong-Tao; Shi, Su-Fei
- Abstract
Transition metal dichalcogenide (TMDC) moiré superlattices, owing to the moiré flatbands and strong correlation, can host periodic electron crystals and fascinating correlated physics. The TMDC heterojunctions in the type-II alignment also enable long-lived interlayer excitons that are promising for correlated bosonic states, while the interaction is dictated by the asymmetry of the heterojunction. Here we demonstrate a new excitonic state, quadrupolar exciton, in a symmetric WSe2-WS2-WSe2 trilayer moiré superlattice. The quadrupolar excitons exhibit a quadratic dependence on the electric field, distinctively different from the linear Stark shift of the dipolar excitons in heterobilayers. This quadrupolar exciton stems from the hybridization of WSe2 valence moiré flatbands. The same mechanism also gives rise to an interlayer Mott insulator state, in which the two WSe2 layers share one hole laterally confined in one moiré unit cell. In contrast, the hole occupation probability in each layer can be continuously tuned via an out-of-plane electric field, reaching 100% in the top or bottom WSe2 under a large electric field, accompanying the transition from quadrupolar excitons to dipolar excitons. Our work demonstrates a trilayer moiré system as a new exciting playground for realizing novel correlated states and engineering quantum phase transitions. The authors observe the signatures of quadrupolar excitons in a WSe2-WS2-WSe2 trilayer moiré superlattice, originating from the hybridization of the WSe2 valence moiré flatbands. They further use electrostatic gating to reveal a hybridized interlayer Mott insulator state, with holes shared between the two WSe2 layers but laterally confined in moiré superlattices.
- Subjects
EXCITON theory; QUANTUM phase transitions; UNIT cell; ELECTRIC fields; ORBITAL hybridization; STARK effect; SUPERRADIANCE
- Publication
Nature Communications, 2023, Vol 14, Issue 1, p1
- ISSN
2041-1723
- Publication type
Article
- DOI
10.1038/s41467-023-40288-9