Electron transport in a HgTe quantum spin Hall bar with periodic electric modulations

We theoretically investigate the electron transport through a quantum spin Hall bar in the presence of periodic potential modulations. We find that the edge states show different behaviors for the periodic electric potential modulation in the proposed structures. The backscattering process can be controlled by tuning the electric potential modulation.

► Rich conductance features will show up as the Rashba spin–orbit interaction (RSOI) strength or barrier height varies.
► Fabry–Perot resonances can be observed due to the interference in the modulation regions.
► Interestingly, the edge states show backscattering process without the applied magnetic field.