Fig. 5: Topological characterization via Wilson loops.
From: Cubic 3D Chern photonic insulators with orientable large Chern vectors
Wilson loops for the system in the Weyl semimetal phase (in blue) and in the cubic 3D CzI phase (in red). Each θ eigenvalue of the WL is related to the WEC in terms of the i-th lattice parameter ∣ai∣ by 2πWECn,i ≡ ∣ai∣θn,i, with ∣ai∣ = ∣a∣ and ∣ai∣ = N∣a∣ for the WS and the 3D CI respectively. a, b Individual photonic WECs: flow in the kx direction on a selected fixed kz plane, for each of the bands lying below the local gap. c, d Net photonic WEC flow, obtained by summing up the contribution of the individual WECs shown in the above panels: the net winding appears now clearly. Source data are provided as a Source Data file.
