Fig. 2: Finite-size circuit model.
a Top view of a stacked 10-layer HK circuit with 2860 nodes. The green and blue segments represent the capacitors CA and CB, respectively, and each node is grounded by capacitors and inductors with the configurations shown in the insets. The finite-size equilateral triangular structure with the zigzag edge was chosen because one requires a uniform onsite admittance for all nodes of the breathing kagome block that appears upon squaring the Laplacian. b Admittances for CA = CZ = CB/2 = 0.5 nF, LA = 30 μH, LB = 7.5 μH, LC = 18 μH, and LG = 21.829 μH. The red, blue, black symbols represent the hinge, surface, bulk states, respectively. Spatial distribution of the wave functions of the normalized hinge state (jn = 3.534 × 10−7 Ω−1) (c), surface state (jn = − 0.0003762 Ω−1) (d), and bulk state (jn = 0.001042 Ω−1) (e).
