Figure 4

Schematic illustration of the manipulation for a perfect edge state in a graphene tube, which is represented by a red circle.
When varying the flux slowly, state (a1) can evolve to (a2) and (a3), where (a2) represents a maximal entangled state. (b1) and (b2) are plots of the fidelities under the control of Gaussian pulse fluxes with several typical σ. Here the time t is in units of 1/Δ.