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

Physical review. B./Physical review. B, vol. 105

Abstract

We investigate a system consisting of one or two topological-insulator leads which are tunnel coupled to a single dot level. The leads are described by the one-dimensional Su-Schrieffer-Heeger model. We show that (topological) edge states cause characteristic features in the dot spectral function, the dot occupation, and the finite-bias current across the dot. As the kinetic energy is quenched in the dot region, local two-particle interactions are of particular relevance there. This motivates us to test whether the aforementioned edge-state features are robust against such interactions; we report here that they are either robust or even enhanced. We conclude that the characteristic features can be used to determine if the leads are in their topologically nontrivial or trivial phase.

Authors 6

1. Martin T. Maurer Aachen Institut für Theorie der Statistischen Physik

   RWTH Aachen University · Jülich Aachen Research Alliance

   Affiliation as printed

   Institut für Theorie der Statistischen Physik, RWTH Aachen University and JARA—Fundamentals of Future Information Technology, 52056 Aachen, Germany

2. Yen‐Ting Lin Aachen Institut für Theorie der Statistischen Physik

   RWTH Aachen University · Jülich Aachen Research Alliance

   Affiliation as printed

   Institut für Theorie der Statistischen Physik, RWTH Aachen University and JARA—Fundamentals of Future Information Technology, 52056 Aachen, Germany

3. Dante Marvin Kennes Aachen Institut für Theorie der Statistischen Physik

   RWTH Aachen University · Jülich Aachen Research Alliance · Max Planck Institute for the Structure and Dynamics of Matter · Center for Free-Electron Laser Science

   Affiliation as printed

   Institut für Theorie der Statistischen Physik, RWTH Aachen University and JARA—Fundamentals of Future Information Technology, 52056 Aachen, Germany

   Max Planck Institute for the Structure and Dynamics of Matter, Center for Free Electron Laser Science, 22761 Hamburg, Germany

4. Mikhail Pletyukhov Aachen Institut für Theorie der Statistischen Physik

   RWTH Aachen University · Jülich Aachen Research Alliance

   Affiliation as printed

   Institut für Theorie der Statistischen Physik, RWTH Aachen University and JARA—Fundamentals of Future Information Technology, 52056 Aachen, Germany

5. Herbert Schoeller Aachen Institut für Theorie der Statistischen Physik

   RWTH Aachen University · Jülich Aachen Research Alliance

   Affiliation as printed

   Institut für Theorie der Statistischen Physik, RWTH Aachen University and JARA—Fundamentals of Future Information Technology, 52056 Aachen, Germany

6. V. Meden Aachen Institut für Theorie der Statistischen Physik

   RWTH Aachen University · Jülich Aachen Research Alliance

   Affiliation as printed

   Institut für Theorie der Statistischen Physik, RWTH Aachen University and JARA—Fundamentals of Future Information Technology, 52056 Aachen, Germany