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arXiv · 1305.5801

Non-polar (11-20) InGaN quantum dots with short exciton lifetimes grown by metal-organic vapor phase epitaxy

Tongtong Zhu·Fabrice Oehler·Benjamin P. L. Reid·Robert M. Emery·Robert A. Taylor·Menno J. Kappers·Rachel A. Oliver
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Abstract

We report on the optical characterization of non-polar a-plane InGaN quantum dots (QDs) grown by metal-organic vapor phase epitaxy using a short nitrogen anneal treatment at the growth temperature. Spatial and spectral mapping of sub-surface QDs have been achieved by cathodoluminescence at 8 K. Microphotoluminescence studies of the QDs reveal resolution limited sharp peaks with typical linewidth of 1 meV at 4.2 K. Time-resolved photoluminescence studies suggest the excitons in these QDs have a typical lifetime of 538 ps, much shorter than that of the c-plane QDs, which is strong evidence of the significant suppression of the internal electric fields.

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Tongtong Zhu, Fabrice Oehler, Benjamin P. L. Reid, Robert M. Emery, Robert A. Taylor, Menno J. Kappers, Rachel A. Oliver. 2013-05-24. Non-polar (11-20) InGaN quantum dots with short exciton lifetimes grown by metal-organic vapor phase epitaxy. https://doi.org/10.1063/1.4812345

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