Quasi bound states in the continuum with few unit cells of photonic crystal slab

Alireza Taghizadeh, Il-Sug Chung

doi:10.1063/1.4990753

Quasi bound states in the continuum with few unit cells of photonic crystal slab

DOI PDF 被引用文献1件

Alireza Taghizadeh

Department of Photonics Engineering (DTU Fotonik), Technical University of Denmark 1 , DK-2800 Kgs. Lyngby, Denmark
Il-Sug Chung

Department of Photonics Engineering (DTU Fotonik), Technical University of Denmark 1 , DK-2800 Kgs. Lyngby, Denmark

抄録

<jats:p>Bound states in the continuum (BICs) in photonic crystal slabs represent the resonances with an infinite quality (Q)-factor, occurring above the light line for an infinitely periodic structure. We show that a set of BICs can turn into quasi-BICs with a very high Q-factor even for two or three unit cell structures. They are explained by a viewpoint of BICs originating from the tight-binding of individual resonances of each unit cell as in semiconductors. Combined with a reciprocal-space matching technique, the microcavities based on quasi-BICs can achieve a Q-factor as high as defect-based PhC microcavities. These results may enable the experimental studies of BICs in a compact platform as well as realizing high-Q mirrorless microcavities.</jats:p>