[20p-E207-1~15] 3.11 Photonic structures and phenomena

[20p-E207-8] Observation of Phase-Reconstruction Near the Optical Weyl Point in a Three-Dimensional Chiral Photonic Crystal

〇(M1)Souma Tamaki¹, Shun Takahashi¹, Kenichi Yamashita¹, Takuya Yamaguchi¹, Tetsuya Ueda¹, Satoshi Iwamoto² (1.Kyoto Inst. of Tech., 2.RCAST/IIS, Univ. of Tokyo)

Keywords:Weyl Point, Photonic Crystal, Phase-Reconstruction

The special propagation characteristics of electromagnetic waves are focused on Dirac points, which are two-dimensional point degeneracy in the photonic band structure, and Weyl points, which is a three-dimensional extension concept thereof. In particular, in a photonic structure in which a Dirac point is formed at a saddle point, an electromagnetic wave does not receive a spatial phase change because the refractive index effectively approaches zero due to its linear dispersion. Therefore, the transmitted wave to the structure with point degeneracy is reconstructed (restored) in phase at the structure end to become a plane wave. However, although there are many reports for the Dirac point of a two-dimensional system, there are no reports of experimentally examining transmitted waves for the Weyl point of the three-dimensional system. So, in this research, we observed the phase reconstruction phenomenon in the vicinity of the Weyl point in the microwave region using dielectric chiral photonic crystals.