Observation of Quadratic (Charge‐2) Weyl Point Splitting in Near‐Infrared Photonic Crystals
Abstract
Weyl points are point degeneracies that occur in momentum space of 3D periodic materials and are associated with a quantized topological charge. Here, the splitting of a quadratic (charge‐2) Weyl point into two linear (charge‐1) Weyl points in a 3D micro‐printed photonic crystal is observed experimentally via Fourier‐transform infrared spectroscopy. Using a theoretical analysis rooted in symmetry arguments, it is shown that this splitting occurs along high‐symmetry directions in the Brillouin zone. This micro‐scale observation and control of Weyl points is important for realizing robust topological devices in the near‐infrared.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 10, 2021
- Source ID
- 10.1002/lpor.202100452
Entities
People
- Alexander Cerjan
- Christina Jörg
- Georg von Freymann
- Jiho Noh
- Mikael C Rechtsman
- Sachin Vaidya
- Shyam Augustine
Organizations
- German Research Foundation
- Office of Naval Research
- Pennsylvania State University
- Sandia National Laboratories
- University of Illinois Urbana–Champaign