Abstract
In 2D Chern insulators, the topology of the bulk states is captured by a topological invariant, the Chern number. The scalar bulk-boundary correspondence (sBBC) relates the change in Chern number across an interface with the number of 1D chiral edge modes at the interface. However, 3D Chern insulators (3D CIs) can be characterized by a Chern vector (Formula presented.) and a more general vector bulk-boundary correspondence (vBBC) is needed to correctly predict the propagation of the surface modes. In this work the possible interfaces between 3D photonic CIs are explored, focusing on possible changes in Chern vector orientation. To formulate a 3D vBBC, a link is derived between the Chern vector discontinuity across an interface and the winding of the surface equifrequency loops on the boundary. Last, it is demonstrated how to correctly predict the number and the propagation direction of topological photonic surface modes in 3D CIs.
Original language | English (US) |
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Article number | 2200475 |
Journal | Advanced Optical Materials |
Volume | 10 |
Issue number | 20 |
DOIs | |
State | Published - Oct 18 2022 |
Keywords
- Chern vectors
- bulk-boundary correspondence
- photonic surface modes
- planar interfaces
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics