Fig. 2: Realization of the minimal ideal photonic Weyl metamaterial.

a Unit cell with in-plane period a = 5 mm and thickness h = 2 mm. The lengths of the long and short arms of the metallic (PEC) structure are 1.1a and 0.5a, respectively. The width of all metallic (PEC) wires is 0.1a, and the thickness is 35 μm. The metallic (PEC) structure is embedded in a magnetized plasma with electron density 2 × 10¹² cm⁻¹ under a 0.5 T static magnetic field B in the x direction. b Bulk BZ with the high-symmetry points [involved in c and d] highlighted by black dots. The two WPs [red and blue dots, observed in d] are located along the Γ−X and Γ−X′ directions. c Simulated band structure along high-symmetry lines when the TRS is respected (B = 0). Three degenerated points are found at the frequency f_n = 24.1 GHz, reminding us of the NL in the k_x–k_y plane. d Same as c but for the broken TRS (B ≠ 0). Two WPs (red and blue dots) are observed at the frequency f_w = 25.1 GHz. e, f 3D views of the band structures in the k_x–k_y plane for the NL and Weyl metamaterials, respectively, wherein the NL and WPs are visualized