Open AccessPhysical mechanism of super-broadband and all-angle self-collimation transmission in photonic crystal with low rotational symmetry
Author(s) -
Liang Wen-Yao,
Yuxia Zhang,
Wuhe Chen
Publication year - 2015
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.64.064209
Subject(s) - photonic crystal , optics , brillouin zone , broadband , collimated light , finite difference time domain method , physics , polarization (electrochemistry) , brewster's angle , photonics , materials science , condensed matter physics , laser , chemistry , brewster
We propose a two-dimensional photonic crystal structure with low rotational symmetry and investigate its band structure characteristics over the whole first Brillouin zone by the plane wave expand method. The physical mechanism of broadband all-angle self-collimation effect and the influence of aspect ratio on the bandwidth are clarified. Furthermore, we obtain the existence criterion for self-collimation modes covering almost the whole fourth band for TE polarization. Especially, there exist two wide flat regions spanning over the first Brillouin zone which exhibit unique properties: one dimension corresponds to broad band from 0.47 to 0.53 (2πc/a), while the other corresponds to all incident angles of 0°–90°. Based on the above unique properties, the broadband all-angle self-collimation propagation with a bandwidth of 187 nm around 1550 nm is demonstrated by the finite-difference time-domain method.