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Abstract Moiré superlattices of semiconducting transition metal dichalcogenides enable unprecedented spatial control of electron wavefunctions, leading to emerging quantum states. The breaking of translational symmetry further introduces a new degree of freedom: high symmetry moiré sites of energy minima behaving as spatially separated quantum dots. We demonstrate the superposition between two moiré sites by constructing a trilayer WSe2/monolayer WS2moiré heterojunction. The two moiré sites in the first layer WSe2interfacing WS2allow the formation of two different interlayer excitons, with the hole residing in either moiré site of the first layer WSe2and the electron in the third layer WSe2. An electric field can drive the hybridization of either of the interlayer excitons with the intralayer excitons in the third WSe2layer, realizing the continuous tuning of interlayer exciton hopping between two moiré sites and a superposition of the two interlayer excitons, distinctively different from the natural trilayer WSe2.
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This content will become publicly available on July 1, 2026
Advanced Characterization of the Spatial Variation of Moiré Heterostructures and Moiré Excitons
Abstract In this short review, an overview of recent progress in deploying advanced characterization techniques is provided to understand the effects of spatial variation and inhomogeneities in moiré heterostructures over multiple length scales. Particular emphasis is placed on correlating the impact of twist angle misalignment, nano‐scale disorder, and atomic relaxation on the moiré potential and its collective excitations, particularly moiré excitons. Finally, future technological applications leveraging moiré excitons are discussed.
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- Award ID(s):
- 2329067
- PAR ID:
- 10638926
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Small
- Volume:
- 21
- Issue:
- 28
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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