Open AccessCreation of large band gap with anisotropic annular photonic crystal slab structure
Author(s) -
Peng Shi,
Kun Huang,
Xueliang Kang,
Yongping Li
Publication year - 2010
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.18.005221
Subject(s) - photonic crystal , slab , optics , rod , materials science , tellurium , anisotropy , band gap , plane wave expansion method , dielectric , yablonovite , condensed matter physics , optoelectronics , physics , photonic integrated circuit , medicine , alternative medicine , pathology , geophysics , metallurgy
A two-dimensional anisotropic annular photonic crystal slab structure composed of circular air holes and dielectric rods with finite thickness in a triangular lattice is presented to achieve an absolute photonic band gap. Positive uniaxial crystal Tellurium is introduced to the structure with the extraordinary axis parallel to the extension direction of rods. The role of each geometric parameter is investigated by employing the conjugate-gradient method. A large mid-gap ratio is realized by the parameter optimization. A flat band called as anomalous group velocity within two large gaps is discovered and can be widely applied in many fields. A hybrid structure with GaAs slab and Te rods is designed to achieve a large gap and demonstrates that the annular structure can improve the gap effectively.