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arXiv · 2002.03215

Observation of a charge-2 photonic Weyl point in the infrared

Sachin Vaidya·Jiho Noh·Alexander Cerjan·Mikael C. Rechtsman
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Abstract

Weyl points are robust point degeneracies in the band structure of a periodic material, which act as monopoles of Berry curvature. They have been at the forefront of research in three-dimensional topological materials (whether photonic, electronic or otherwise) as they are associated with novel behavior both in the bulk and on the surface. Here, we present the experimental observation of a charge-2 photonic Weyl point in a low-index-contrast photonic crystal fabricated by two-photon polymerization. The reflection spectrum obtained via Fourier Transform Infrared (FTIR) spectroscopy closely matches simulations and shows two bands with quadratic dispersion around a point degeneracy. This work provides a launching point towards all-dielectric, low-contrast three-dimensional photonic topological devices.

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Sachin Vaidya, Jiho Noh, Alexander Cerjan, Mikael C. Rechtsman. 2020-02-08. Observation of a charge-2 photonic Weyl point in the infrared. https://doi.org/10.1103/physrevlett.125.253902

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