Formation mechanism of guided resonances and bound states in the continuum in photonic crystal slabs

We develop a formalism, based on the mode expansion method, to describe the guided resonances and bound states in the continuum (BICs) in photonic crystal slabs with one-dimensional periodicity. This approach provides analytic insights to the formation mechanisms of these states: the guided resonanc...

Full description

Bibliographic Details
Main Authors: Gao, Xingwei, Chen, Hongsheng, Hsu, Chia Wei, Zhen, Bo, Lin, Xiao, Joannopoulos, John, Soljacic, Marin
Other Authors: Massachusetts Institute of Technology. Institute for Soldier Nanotechnologies
Format: Article
Language:en_US
Published: Nature Publishing Group 2017
Online Access:http://hdl.handle.net/1721.1/108431
https://orcid.org/0000-0002-7572-4594
https://orcid.org/0000-0002-7244-3682
https://orcid.org/0000-0002-7184-5831
Description
Summary:We develop a formalism, based on the mode expansion method, to describe the guided resonances and bound states in the continuum (BICs) in photonic crystal slabs with one-dimensional periodicity. This approach provides analytic insights to the formation mechanisms of these states: the guided resonances arise from the transverse Fabry–Pérot condition, and the divergence of the resonance lifetimes at the BICs is explained by a destructive interference of radiation from different propagating components inside the slab. We show BICs at the center and on the edge of the Brillouin zone protected by symmetry, BICs at generic wave vectors not protected by symmetry, and the annihilation of BICs at low-symmetry wave vectors.