Figure 6
Impurity substitutions along the zigzag graphene ribbon in a supercell of 11 armchair chains shown in (a). A boron atom substitutes a carbon atom at the n-th position (shown by a green ball at n = 14). Panels (b,c) show the gap evolution with respect to the substitutions at the n-th position for the B and N cases, respectively. Filled blue (red) dots correspond to the spin up (down) gaps. For comparison, the bandgaps of the pristine systems with perfect interfaces are shown with dotted lines, blue and red denoting up and down channels, respectively.
