2015/06/19 by Maria Grazia Marciani, M. Marciani, Henning Schomerus +2 · 4 citations
Physics and Astronomy · #Bound state #Condensed matter physics #Conductance #Coupling (piping) #MAJORANA #Materials science #Nanotechnology #Physics #Proximity effect (electron beam lithography) #Quantum and electron transport phenomena #Quantum many-body systems #Quantum mechanics #Scattering #Superconductivity #Topological Materials and Phenomena #Topology (electrical circuits) #cond-mat.mes-hall #cond-mat.supr-con #nlin.CD
paper · pdf · doi:10.1016/j.physe.2015.10.030
published in Physica E Low-dimensional Systems and Nanostructures 77, 54-64 (Elsevier BV) · Contribution for the special issue of Physica E in memory of Markus Büttiker. 13 pages, 7 figures
arxiv created 2015/06/19 · openalex publication_date 2015/11/03 · arxiv updated 2016/06/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We calculate the joint distribution P(S,Q) of the scattering matrix S and time-delay matrix Q=-iℏ S^† dS/dE of a chaotic quantum dot coupled by point contacts to metal electrodes. While S and Q are statistically independent for ballistic coupling, they become correlated for tunnel coupling. We relate the ensemble averages of Q and S and thereby obtain the average density of states at the Fermi level. We apply this to a calculation of the effect of a tunnel barrier on the Majorana resonance in a topological superconductor. We find that the presence of a Majorana bound state is hidden in the density of states and in the thermal conductance if even a single scattering channel has unit tunnel probability. The electrical conductance remains sensitive to the appearance of a Majorana bound state, and we calculate the variation of the average conductance through a topological phase transition.