Mardi 26 mars 2013 à 10h15
Salle 234, Ecole de Physique

Transport properties of generic topological insulator edge states

Thomas Schmidt, University of Basel

The edge states of two-dimensional topological insulators have the extraordinary property of being helical: electrons with opposite spins propagate in opposite directions. The helicity gives rise to characteristic transport properties, e.g., the absence of elastic backscattering if the system is time-reversal invariant and the resulting quantized edge conductance. In this talk, I will discuss how the concept of helical liquids can be generalized to systems in which the electron spin is not a good quantum number. Such ``generic' helical liquids exist, e.g., in topological insulators with Rashba spin-orbit coupling. This absence of the spin symmetry, in connection with electron-electron interactions, has profound implications for the edge state transport.