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DOE OSTI · 2421432

Epitaxial hexagonal boron nitride with high quantum efficiency

Laleyan, David Arto·Lee, Woncheol·Zhao, Ying·Wu, Yuanpeng·Wang, Ping·Song, Jun·Kioupakis, Emmanouil·Mi, Zetian
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Abstract

Two-dimensional (2D) hexagonal boron nitride (h-BN) is one of the few materials showing great promise for light emission in the far ultraviolet (UV)-C wavelength, which is more effective and safer in containing the transmission of microbial diseases than traditional UV light. In this report, we observed that h-BN, despite having an indirect energy bandgap, exhibits a remarkably high room-temperature quantum efficiency (~60%), which is orders of magnitude higher than that of other indirect bandgap material, and is enabled by strong excitonic effects and efficient exciton-phonon interactions. This study offers a new approach for the design and development of far UV-C optoelectronic devices as well as quantum photonic devices employing 2D semiconductor active regions.

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36 MATERIALS SCIENCEBethe-Salpeter equationDensity functional theoryExcitonic effectsLasersLocal density approximationsOptoelectronic devicesPhononsQuantum efficiencySemiconductorsUltraviolet light

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Laleyan, David Arto, Lee, Woncheol, Zhao, Ying, Wu, Yuanpeng, Wang, Ping, Song, Jun, Kioupakis, Emmanouil, Mi, Zetian. 2023-05-01. Epitaxial hexagonal boron nitride with high quantum efficiency. https://doi.org/10.1063/5.0142242

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36 MATERIALS SCIENCE↗