Polarization ratio enhancement of a-plane GaN light emitting diodes by asymmetric two-dimensional photonic crystals. - Yen Chou; Hsiang-Wei Li; Yu-Feng Yin; Yu-Ting Wang; Yen-Chen Lin; Da-Wei Lin; Yuh-Renn Wu; Hao-Chung Kuo; Jian Jang Huang (Journal of Applied Physics, 2014)