光学束缚态在连续谱中的拓扑性质。

Topological nature of optical bound states in the continuum.

机构信息

Department of Physics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.

Department of Physics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA and Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA.

出版信息

Phys Rev Lett. 2014 Dec 19;113(25):257401. doi: 10.1103/PhysRevLett.113.257401. Epub 2014 Dec 18.

DOI:10.1103/PhysRevLett.113.257401

PMID:25554906

Abstract

Optical bound states in the continuum (BICs) have recently been realized in photonic crystal slabs, where the disappearance of out-of-plane radiation turns leaky resonances into guided modes with infinite lifetimes. We show that such BICs are vortex centers in the polarization directions of far-field radiation. They carry conserved and quantized topological charges, defined by the winding number of the polarization vectors, which ensure their robust existence and govern their generation, evolution, and annihilation. Our findings connect robust BICs in photonics to a wide range of topological physical phenomena.

摘要

光学束缚态在连续体（BIC）最近已经在光子晶体平板中实现，其中平面外辐射的消失将泄漏共振转变为具有无限寿命的导模。我们表明，这些 BIC 是远场辐射的偏振方向中的旋涡中心。它们携带守恒和量子化的拓扑电荷，由偏振矢量的缠绕数定义，这确保了它们的稳健存在，并控制着它们的产生、演化和湮灭。我们的发现将光子学中的稳健 BIC 与广泛的拓扑物理现象联系起来。