Open AccessTwo-dimensional photonic-crystal-slab channel-drop filter with flat-top response
Author(s) -
Yoshihiro Akahane,
Tanemasa Asano,
Hitomichi Takano,
Biao Song,
Yoshinori Takana,
Susumu Noda
Publication year - 2005
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/opex.13.002512
Subject(s) - photonic crystal , optics , materials science , drop (telecommunication) , slab , finite difference time domain method , bandwidth (computing) , optical filter , coupled mode theory , filter (signal processing) , wavelength division multiplexing , wavelength , refractive index , physics , telecommunications , geophysics , computer science , computer vision
We report a theoretical and experimental study of a channel drop filter with two cascaded point-defects between two line-defects in a two-dimensional photonic-crystal slab. Using coupled-mode analysis and a three-dimensional finite-difference time-domain method, we design a filter to engineer the line shape of the drop spectrum. A flat-top and sharp roll-off response is theoretically and experimentally achieved by the designed and fabricated filters. Furthermore, we theoretically demonstrate that drop efficiency is increased dramatically, up to 93%, by introducing hetero-photonic-crystals. We also describe a method to modify the bandwidth of the spectrum.