Majorana Bound State Leakage to Impurity in Su-Schrieffer-Heeger-Rashba Scenario

A. Kobiałkaa, A. Ptokb aInstitute of Physics, Maria Curie-Skłodowska University, Pl. M. Skłodowskiej-Curie 1, 20-031 Lublin, Poland bInstitute of Nuclear Physics, Polish Academy of Sciences, W.E. Radzikowskiego 152, 31-342 Kraków, Poland

Full Text PDF

We show the anomalous features of the Majorana bound state leakage in the situation where topological Rashba nanowire is dimerized according to the Su-Schrieffer-Heeger scenario and an impurity is present at one of the ends of the system. We find that two topological branches: the usual, indigenous to the Rashba nanowire, and the dimerized one, existing as a result of the Su-Schrieffer-Heeger dimerization of the nanowire, have different asymmetry of spin polarization that can be explained by the opposite order of bands taking part in topological transitions. Additionally, the introduction of an impurity to the dimerized nanowire influences the leakage of the Majorana bound states into the trivial impurity due to the emergence of the Andreev bound states that behave differently depending on whether the system is or is not in a topological phase. This results in the pinning of zero energy states to the impurity site for some range of parameters.

DOI:10.12693/APhysPolA.138.673 topics: Su-Schrieffer-Heeger, SSH, Rashba nanowire, Majorana bound states