Dirac Cones for Point Scatterers on a Honeycomb Lattice
Dirac Cones for Point Scatterers on a Honeycomb Lattice
We investigate the spectrum and the dispersion relation of the Schr\"odinger operator with point scatterers on a triangular lattice and a honeycomb lattice. We prove that the low-level dispersion bands have conic singularities near Dirac points, which are the vertices of the first Brillouin Zone. The existence of such conic …