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Title: Epitaxial hexagonal boron nitride with high quantum efficiency
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.  more » « less
Award ID(s):
2118809
PAR ID:
10595058
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
APL Materials
Volume:
11
Issue:
5
ISSN:
2166-532X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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