arXiv subjects

Sukkoo Jung

Publications and source records attributed to Sukkoo Jung.

2 recordsLinked to original sources

arXiv2013

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

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.

cond-mat.mes-hall↗

arXiv2013

Defect recombination induced by density-activated carrier diffusion in nonpolar InGaN quantum wells

We report on the observation of carrier-diffusion-induced defect emission at high excitation density in a-plane InGaN single quantum wells. When increasing excitation density in a relatively high regime, we observed the emergence of defect-related emission together with a significant reduction in bandedge emission efficiency. The experimental results can be well explained with the density-activated carrier diffusion from localized states to defect states. Such a scenario of density-activated defect recombination, as confirmed by the dependences of photoluminescence on the excitation photon energy and temperature, is a plausible origin of efficiency droop in a-plane InGaN quantum-well light-emitting diodes.

cond-mat.mes-hall↗