Abstract
We investigate two types of transport phenomena in two-dimensional time-reversal-invariant topological insulators, both focusing on the effect of a weak magnetic field B. We build minimal models, based on scattering theory, for the problems and obtain simple but nontrivial results. In particular, we find that the localization length of the edge states is proportional to B-2 when B is small, and saturates to a constant when B is sufficiently large. On the other hand, the current cross-correlation in a Hall-bar setup is featured by a robust peak at B=0 where the correlation simply vanishes because of the time-reversal symmetry. We make both qualitative predictions and quantitative estimations which are readily checked in experiments.
Coffee and tea will be served 20 minutes prior to the seminar.