The novel topological insulator material has provided the physical foundation for the dissipationless spin transport, possibly constructed the brand-new spintronic devices. The edge state of the topological insulator shows unusual helical feature due to the electron spin-momentum locking. Using the Luttinger liquid theory and nonequilibium Green function, the quantum transport in a quantum spin Hall bar with three quantum point contacts ( QPCs) was studied. The currents display very different pump frequency dependence for weak and strong e-e inter-action. These unique properties were induced b...
