Edge magnetism of Heisenberg model on honeycomb lattice

eld-theory description for the edge magnon and nd its dynamics is captured by the one-dimensional relativistic Klein-Gordon equation. It is intriguing that the boundary eld theory for the edge magnon is tied up with its bulk counterpart, described by the two-dimensional KleinGordon equation. Furthermore, we also reveal how the parity symmetry relates evanescent modes on opposite edges in a honeycomb nanoribbon. By employing alternative methods, including Schwinger bosons and density-matrix renormalization group, we also demonstrate that the relativistic edge magnon is robust even when the Neel order in the bulk is destroyed by quantum