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Updated: Dec 14, 2025
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
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Coupling Interlayer Excitons to Whispering Gallery Modes in van der Waals Heterostructures
Ronja Khelifa1, Patrick Back1, Nikolaus Flöry1
1Photonics Laboratory, ETH Zürich, 8093 Zürich, Switzerland.
Nano Letters
|July 22, 2020
Summary
Engineered van der Waals heterostructures in hexagonal boron nitride (h-BN) disk resonators enable cavity-coupled emission from transition metal dichalcogenide interlayer excitons. This breakthrough advances on-chip van der Waals photonics.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Van der Waals heterostructures offer tunable optoelectronic properties.
- Two-dimensional materials enable novel device architectures.
- Cavity coupling enhances light-matter interactions.
Purpose of the Study:
- To demonstrate cavity-coupled emission from interlayer excitons in transition metal dichalcogenide heterobilayers.
- To engineer on-chip van der Waals photonic devices using hexagonal boron nitride (h-BN) resonators.
- To investigate the impact of heterostructure integration on optical properties.
Main Methods:
- Fabrication of waveguide-coupled disk resonators from hexagonal boron nitride (h-BN).
- Integration of a molybdenum selenide-tungsten selenide (MoSe2-WSe2) heterobilayer within the h-BN structure.
- Characterization of cavity-coupled emission from interlayer excitons.
Main Results:
- Successful demonstration of cavity-coupled emission from MoSe2-WSe2 interlayer excitons.
- Maximized mode overlap and coupling strength by positioning active materials in high optical field regions.
- Unaffected resonator quality factor due to weak reabsorption of interlayer exciton emission.
Conclusions:
- Waveguide-coupled h-BN disk resonators are effective for on-chip van der Waals photonics.
- This platform enables efficient light-matter interaction for interlayer excitons.
- The approach holds promise for developing novel optoelectronic devices.
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