We highlight the fact that two-dimensional materials with Dirac-like low energy band structures and spin-orbit coupling will produce linearly dispersing topologically protected Jackiw–Rebbi modes at interfaces where the Dirac mass changes sign. These modes may support persistent spin or valley currents parallel to the interface, and the exact arrangement of such topologically protected currents depends crucially on the details of the spin-orbit coupling in the material. As
examples, we discuss buckled two-dimensional hexagonal lattices such as silicene or germanene, and transition metal dichalcogenides such as MoS2 .

David Abergel is currently an Assistant Professor at Nordita in Stockholm, Sweden. He is primarily interested in the electrical, optical, and thermodynamic properties of Dirac materials. He received his M.Sci degree in Theoretical Physics with Mathematics from Lancaster University, and a Ph.D. in Physics, also from Lancaster University. After finishing his Ph.D, he had postdoctoral positions at the University of Manitoba, Canada, and the University of Maryland, USA.