What limits the efficiency of GaN-based superluminescent light-emitting diodes (SLEDs)?

  • Joachim PiprekEmail author


Gallium-nitride-based SLEDs are attractive light sources for augmented reality displays and other applications. However, the electrical-to-optical power conversion efficiency (PCE) of SLEDs is still far below the record-high values reported for LEDs. Utilizing advanced numerical device simulation, this paper investigates the internal physical processes that cause the low PCE of SLEDs. The poor hole conductivity strongly reduces the electrical efficiency, similar to laser diodes. However, in contrast to laser diodes, the rising carrier density in the active layers is identified as main reason for enhanced Auger recombination that severely limits the internal quantum efficiency. Design improvement options are demonstrated.


Superluminescent light-emitting diode SLED Laser diode InGaN/GaN Power conversion efficiency Auger recombination Hole conductivity Self-heating 



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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.NUSOD Institute LLCNewarkUSA

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