Photonic band structures of annular photonic-crystal (APC) silicon-on-insulator (SOI) asymmetric slabs with finite thickness were investigated by the three-dimensional plane-wave expansion method. The results show that for a broad range of air-volume filling factors, APC slabs can exhibit a significantly larger bandgap than conventional circular-hole photonic-crystal (PC) slabs. Bandgap enhancements over conventional air hole PC SOI slabs as large as twofold are predicted for low air-volume filling factors below 15%. This desirable behavior suggests a potential for APC SOI slabs to serve as the basis of various optical cavities, waveguides, and mirrors.
© 2011 Optical Society of America
Original Manuscript: March 1, 2011
Revised Manuscript: April 29, 2011
Manuscript Accepted: May 1, 2011
Published: June 8, 2011
Jin Hou, D. S. Citrin, Huaming Wu, Dingshan Gao, and Zhiping Zhou, "Enhanced bandgap in annular photonic-crystal silicon-on-insulator asymmetric slabs," Opt. Lett. 36, 2263-2265 (2011)