Quantum dot coupled to topological insulators: The role of edge states

We investigate a system consisting of one or two topological-insulator leads\nwhich are tunnel coupled to a single dot level. The leads are described by the\none-dimensional Su-Schrieffer-Heeger model. We show that (topological) edge\nstates cause characteristic features in the dot spectral function, the dot\noccupation, and the finite-bias current across the dot. As the kinetic energy\nis quenched in the dot region, local two-particle interactions are of\nparticular relevance there. This motivates us to test whether the\naforementioned edge-state features are robust against such interactions; we\nreport here that they are either robust or even enhanced. We conclude that the\ncharacteristic features can be used to determine if the leads are in their\ntopologically non-trivial or trivial phase.\n