Quantum pumping through the surface states of a topological insulator

We investigate quantum charge pumping through the surface states of a topological insulator (TI), i.e., ${\mathrm{Bi}}₂{\mathrm{Te}}₃$. We consider a device with two oscillating potentials for the generation of a dc current in the adiabatic pumping regime. Applying the exchange magnetic field, we show that the device can work as a memory read-out. Also, we show that by applying a static gate voltage the pumping device can work as a field-effect transistor. In addition, the pumped current obtained in our proposed device is significantly (more than three orders of magnitude) greater than the pumped current obtained previously for TI-based devices. These properties show that ${\mathrm{Bi}}₂{\mathrm{Te}}₃$ can be considered a good candidate for the fabrication of nanoelectronic devices based on TI as well as low-power and low-energy consumption devices in quantum computing.