FDTD simulation and analysis of the focusing effect in2D photonic crystals

• Main Authors: You-Ling Weng, 翁佑菱
• Other Authors: 曾雪峰
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/61502647063147641928

碩士 === 臺灣大學 === 光電工程學研究所 === 95 === We investigate the focusing effect in 2D hexagonal photonic crystal (PhC) slab with an effective negative refraction. The effective negative refraction of PhC does not guarantee the existence of left-handed meta-material, so amplification of the evanescent modes is not observed. In this thesis, 2D PhC equi-frequency contour is used to calculate the effective refraction index. We present the point source image properties in 2D PhC slab with uniform effective negative refraction index for various angles by employing the finite-difference time-domain (FDTD) technique. It is shown that the diffraction limit is not overcome by the PhC lens and large angle incident waves are mostly total reflected. The focusing properties of the photonic crystal slab are mainly due to the negative refraction effect, rather than the self-collimation effect.