Electron interferometry and quantum spin Hall phase in silicene

We discuss devices for detection of the topological insulator phase based on the two-path electron interference. For that purpose we consider buckled silicene, for which a local energy gap can be opened by a vertical electric field to close one of the interference paths and for which the quantum spin Hall insulator conditions are controlled by the Fermi energy. In quantum spin Hall phase the interference is absent due to the separation of the spin currents, and the conductance of the devices include sharp features related to localized resonances. In the normal transport conditions the two-path interference produces regular Aharonov-Bohm oscillations in the external magnetic field.