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arXiv · 1310.2004

Reducing the efficiency droop by lateral carrier confinement in InGaN/GaN quantum-well nanorods

Chentian Shi·Chunfeng Zhang·Fan Yang·Min Joo Park·Joon Seop Kwak·Sukkoo Jung·Yoon-Ho Choi·Xiaoyong Wang·Min Xiao
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Abstract

Efficiency droop is a major obstacle facing high-power application of InGaN/GaN quantum-well (QW) light-emitting diodes. In this letter, we report the suppression of efficiency droop induced by density-activated defect recombination in nanorod structure of a-plane InGaN/GaN QWs. In the high carrier density regime, the retained emission efficiency in a dry-etched nanorod sample is observed to be over two times higher than that in its parent QW sample. We further argue that the improvement is a combined effect of the amendment contributed by lateral carrier confinement and the deterioration made by surface trapping.

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Chentian Shi, Chunfeng Zhang, Fan Yang, Min Joo Park, Joon Seop Kwak, Sukkoo Jung, Yoon-Ho Choi, Xiaoyong Wang, Min Xiao. 2013-10-08. Reducing the efficiency droop by lateral carrier confinement in InGaN/GaN quantum-well nanorods. https://doi.org/10.1364/oe.22.00a790

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