Direct observation of topological surface-state arcs in photonic metamaterials

Research output: Contribution to journalArticle

Authors

  • Biao Yang
  • Qinghua Guo
  • Ben Tremain
  • Lauren E. Barr
  • Yuanjiang Xiang
  • Dianyuan Fan
  • Alastair P. Hibbins

Colleges, School and Institutes

Abstract

The discovery of topological phases has introduced new perspectives and platforms for various interesting physics originally investigated in quantum contexts and then, on an equal footing, in classic wave systems. As a characteristic feature, nontrivial Fermi arcs, connecting between topologically distinct Fermi surfaces, play vital roles in the classification of Dirac and Weyl semimetals, and have been observed in quantum materials very recently. However, in classical systems, no direct experimental observation of Fermi arcs in momentum space has been reported so far. Here, using near-field scanning measurements, we show the observation of photonic topological surface-state arcs connecting topologically distinct bulk states in a chiral hyperbolic metamaterial. To verify the topological nature of this system, we further observe backscattering-immune propagation of a nontrivial surface wave across a three-dimension physical step. Our results demonstrate a metamaterial approach towards topological photonics and offer a deeper understanding of topological phases in three-dimensional classical systems.

Details

Original languageEnglish
Article number97
JournalNature Communications
Volume8
Early online date21 Jul 2017
Publication statusE-pub ahead of print - 21 Jul 2017

Keywords

  • Metamaterials, Microwave photonics, Sub-wavelength optics