Photonic crystal used to increase extraction efficiencyof ZnO light-emitting diodes


  • Piotr Kowalczewski Institute of Physics, Technical University of Lodz
  • Włodzimierz Nakwaski Institute of Physics, Technical University of Lodz
  • Robert P. Sarzała Institute of Physics, Technical University of Lodz



Low extraction efficiency following a low angle of total internal reflection at the output surface of simple light-emitting diodes (LEDs) considerably limits their performance and reduces their possible applications. From among various methods used to enhance extraction of radiation from LEDs manufactured from high index-of- refraction materials, an application of photonic crystals seems to be quite effective and relatively simple technologically. In the present paper, the FDTD approach is used to study the performance of a ZnO LED. As compared with a simple planar ZnO LED structure, the application of an optimized photonic crystal enables in this case an enormous increase in extraction efficiency by more than thirteen times.

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How to Cite

P. Kowalczewski, W. Nakwaski, and R. P. Sarzała, “Photonic crystal used to increase extraction efficiencyof ZnO light-emitting diodes”, Photonics Lett. Pol., vol. 2, no. 4, pp. pp. 186–188, Dec. 2010.