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Highly efficient, deep-ultraviolet luminescence in hBN moiré quantum wells
Chengyun Hong1,2, Fangzhou Zhao3, Su-Beom Song2
1Center for van der Waals Quantum Solids, Institute for Basic Science (IBS), Pohang, Republic of Korea.
Science (New York, N.Y.)
|March 19, 2026
Summary
Twisted hexagonal boron nitride (hBN) creates moiré quantum wells that emit intense deep-ultraviolet light. Twist angle controls luminescence energy and efficiency, outperforming conventional materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Optics
Background:
- Twisted van der Waals (vdW) semiconductors form moiré superlattices, enabling control over quantum states.
- Hexagonal boron nitride (hBN) is a key vdW material with unique electronic properties.
Purpose of the Study:
- To investigate the formation and optical properties of moiré quantum wells (QWs) in twisted hBN.
- To explore the potential of hBN moiré QWs for deep-ultraviolet (DUV) light emission.
Main Methods:
- Fabrication of twisted bilayer hBN structures.
- Characterization of moiré superlattices using optical and electrical methods.
- Measurement of deep-ultraviolet luminescence spectra and efficiency.
Main Results:
- Successfully created hBN moiré QWs within a 3D vdW structure.
- Observed strong confinement of charge carriers via optical excitation and electrical injection.
- Achieved intense DUV luminescence (215-240 nm), exceeding conventional AlGaN QWs by over tenfold.
- Demonstrated tunability of luminescence energy and efficiency via twist angle control.
Conclusions:
- Twisted hBN moiré QWs offer a novel platform for efficient DUV light generation.
- This approach provides a tunable and high-performance alternative to existing DUV emitters.
- The findings open new avenues for optoelectronic devices operating in the DUV spectrum.
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