Electronic properties of SnTe-class topological crystalline insulator materials
Wang Jianfeng1, Wang Na1, Huang Huaqing1, Duan Wenhui1, 2, 3, †, 
(a) Schematic design of a dual-gated heterostructure tuned by the electric field. The incident helicity-degenerate Dirac electrons emitted from the source, and the transmitted helical electron waves are detected by the STM probe. (b) Pronounced helicity filtering when the Fermi level crosses the upper Dirac point. The colorful arrows illustrate the spin orientations at different transmission angles, where the color scale gives the out-of-plane spin component.[
