We analyze the origin of the fake modes introduced by the plane wave expansion method with three-dimension (3D) supercell approximation. Through the detailed analysis of the energy distribution of fake modes and real modes, we propose the plane wave expansion–three planar-slab waveguides method to remove the fake modes and obtain the fake mode free band structure of a two-dimensional air hole photonic crystal slab. To the best of our knowledge, this is the first time that such a fake mode free photonic crystal band structure is presented. Our method is also definitely useful in designing other 3D devices.
© 2011 Optical Society of America
Original Manuscript: December 3, 2010
Revised Manuscript: March 30, 2011
Manuscript Accepted: April 13, 2011
Published: July 20, 2011
Bin Jiang, Wenjun Zhou, Wei Chen, Anjin Liu, and Wanhua Zheng, "Improved fake mode free plane wave expansion method," Opt. Lett. 36, 2788-2790 (2011)