Surface states in crystals with low-index surfaces*
Wang Hui-Pinga), Tao Rui-Baoa),b)
       
(a) The schematic illustration of the lattice structure of a semi-infinite 2D crystal. (b)–(d) The energy spectrum of bulk states and edge states obtained in terms of the exact diagonalization method (blue line), while the dispersion relation of edge states given through TMM (red dash-line) in panels (b) and (c). Panels (b) and (c) show the presence of edge states when the symmetric hopping from the 2NN CPs is considered. (d) The presence of the asymmetric hopping from the 2NN CPs will be favorable to generate edge states. (b) . (c) and . (d) , t 3 = 0.4 t 1, and . For all results we use V A = −1.0 t 1 and V B = 1.5 t 1.