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Published on: August 17, 2017
Supermoiré-Trapped Quadrupolar Exciton
Anish Kumar1, Suman Chatterjee1, Kenji Watanabe2
1Department of Electrical Communication Engineering, Indian Institute of Science, Bangalore560012, India.
Nano Letters
|August 12, 2026
Summary
The supermoiré effect in trilayer heterostructures enables robust formation of quadrupolar excitons, overcoming challenges from twist-angle mismatches. This discovery facilitates exploration of complex excitonic states in multilayered materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Optics
Background:
- Moiré-trapped dipolar interlayer excitons in heterobilayers are key for studying interaction-driven phenomena.
- Extending to trilayers reveals multipolar excitons, a superposition of vertically aligned phase-coherent excitons.
- Experimental challenges include twist-angle mismatches degrading Coulomb coupling.
Purpose of the Study:
- To investigate the role of the supermoiré effect in forming quadrupolar excitons in hetero-trilayer systems.
- To demonstrate the creation of electric field tunable multilevel hybridized quadrupolar states.
- To show reduced sensitivity to precise angle alignment for complex excitonic states.
Main Methods:
- Theoretical proposal utilizing the supermoiré effect in a WS2/WSe2/WS2 stack.
- Analysis of interactions between confined levels at top and bottom moiré interfaces.
- Investigation of electric field tunability of hybridized bright and dark quadrupolar states.
Main Results:
- The supermoiré effect creates periodic pockets of vertically aligned atomic registries.
- These pockets facilitate the formation of trapped quadrupolar excitons.
- Multilevel hybridized bright and dark quadrupolar states were observed and shown to be electric field tunable.
Conclusions:
- The supermoiré effect is critical for the formation of quadrupolar excitons in multilayered heterostructures.
- Reduced sensitivity to precise angle alignment simplifies experimental realization.
- This work opens avenues for exploring complex excitonic states in advanced layered materials.
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