Extended Data Fig. 4: Generalized multipole chiral numbers used for describing the topological phase of Cn-symmetric disclination lattices.
From: Topological orbital angular momentum extraction and twofold protection of vortex transport
a Schematic illustration showing the definition of coordinate axes in the three groups of a nontrivial C3-symmetric disclination lattice marked by dash-dotted lines. b1, c1 Topological invariant of the multipole chiral number \(N\), calculated for a C3-symmetric disclination lattice and for the \(l=1\) (b1) and \(l=2\) (c1) vortex modes. b2, c2 Corresponding calculations for a C4-symmetric lattice, and b3, c3 for a C5-symmetric lattice.
