High optical polarization ratio from semipolar (2021) blue-green InGaN/GaN light-emitting diodes

Yuji Zhao, Shinichi Tanaka, Qimin Yan, Chia Yen Huang, Roy B. Chung, Chih Chien Pan, Kenji Fujito, Daniel Feezell, Chris G. Van De Walle, James S. Speck, Steven P. Denbaars, Shuji Nakamura

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The optical polarization ratio of spontaneous emission was investigated by electroluminescence measurements for semipolar (2021) InGaN/GaN light-emitting diodes, covering the blue to green spectral range. Devices fabricated on semipolar (2021) substrates exhibit polarization ratios ranging from 0.46 at 418 nm to 0.67 at 519 nm. These polarization ratios are significantly higher than those reported on semipolar (2021) devices. The valence band energy separation is extracted from spectral measurements and is consistent with the increased polarization ratio and theoretical predictions. Quantum well interdiffusion induced valence band mixing is suggested as a possible explanation for the low experimental value of polarization ratio observed for the (2021) devices.

Original languageEnglish (US)
Article number051109
JournalApplied Physics Letters
Issue number5
StatePublished - Aug 1 2011


ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

Zhao, Y., Tanaka, S., Yan, Q., Huang, C. Y., Chung, R. B., Pan, C. C., Fujito, K., Feezell, D., Van De Walle, C. G., Speck, J. S., Denbaars, S. P., & Nakamura, S. (2011). High optical polarization ratio from semipolar (2021) blue-green InGaN/GaN light-emitting diodes. Applied Physics Letters, 99(5), [051109]. https://doi.org/10.1063/1.3619826