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Spin-1 Weyl Points in Isotropic Chiral Metamaterials

Ekin Gunes Ozaktas and Shanhui Fan*

  • Department of Electrical Engineering and Ginzton Laboratory, Stanford University, Stanford, California 94305, USA

  • *Contact author: shanhui@stanford.edu
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Phys. Rev. Lett. 137, 103801 – Published 1 September, 2026

DOI: https://doi.org/10.1103/7ty7-d15f

Abstract

We show that an isotropic medium with broken inversion symmetry can exhibit spin-1 Weyl points with a charge of 2. Such points are protected by SO(3) rotational symmetry (isotropy). We study such points in three different systems: a homogeneous chiral Lorentz medium, a periodic chiral metamaterial with point group symmetry, and a random chiral metamaterial with statistical isotropy. We further discuss how such points can be observed through reflectance and transmittance spectra. Our results demonstrate that nontrivial topology can be obtained in isotropic metamaterials, including self-assembled systems.

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Phys. Rev. Lett. 137, 103801– Published 1 September, 2026
  • Received 6 April 2026
  • Revised 6 July 2026
  • Accepted 4 August 2026
Article part of CHORUS
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