[摘要]：Light-emitting diodes (LEDs) were fabricated in gallium nitride with two embedded photonic crystals (PhCs), creating a waveguide with a highly confined, strongly excited, and well-extracted fundamental mode. This structure improves upon previous PhC LED designs by reducing the extraction length of the fundamental mode and establishing a path to designs with very low absorption losses. Optical output was measured with angular-resolved electroluminescence. The extraction length of the fundamental mode was measured to be 21-39 mu m along the PhCs' Gamma-M directions, which is much shorter than values reported for single-PhC devices. This structure opens the way to more efficient LEDs and lasers. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4705735]
