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arXiv · 1907.02303

Carbon dimer defect as a source of the 4.1 eV luminescence in hexagonal boron nitride

Mazena Mackoit-Sinkeviciene·Marek Maciaszek·Chris G. Van de Walle·Audrius Alkauskas
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Abstract

We propose that the carbon dimer defect in hexagonal boron nitride gives rise to the ubiquitous narrow luminescence band with a zero-phonon line of 4.08 eV (usually labeled the 4.1 eV band). Our first-principles calculations are based on hybrid density functionals that provide a reliable description of wide band-gap materials. The calculated zero-phonon line energy of 4.3 eV is close to the experimental value, and the deduced Huang-Rhys factor of ${S \approx 2.0}$, indicating modest electron-phonon coupling, falls within the experimental range. The optical transition occurs between two localized $π$-type defects states, with a very short radiative lifetime of 1.2 nanoseconds, in very good accord with experiments.

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Mazena Mackoit-Sinkeviciene, Marek Maciaszek, Chris G. Van de Walle, Audrius Alkauskas. 2019-11-25. Carbon dimer defect as a source of the 4.1 eV luminescence in hexagonal boron nitride. https://doi.org/10.1063/1.5124153

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