Transport signatures of a junction between a quantum spin Hall system and a chiral topological superconductor

verfasst von: E. G. Novik, B. Trauzettel, P. Recher
Abstract: We investigate transport through a normal-superconductor (NS) junction made from a quantum spin Hall (QSH) system with helical edge states and a two-dimensional (2D) chiral topological superconductor (TSC) having a chiral Majorana edge mode. We employ a two-dimensional extended four-band model for HgTe-based quantum wells in a magnetic (Zeeman) field and subject to s-wave superconductivity. We show using the Bogoliubov-de Gennes scattering formalism that this structure provides a striking transport signal of a 2D TSC. As a function of the sample width (or Fermi energy) the conductance resonances go through a sequence of 2e2/h (nontrivial phase) and 4e2/h plateaux (trivial phase) which fall within the region of a nonzero Chern number (2D limit) as the sample width becomes large. These signatures are a manifestation of the topological nature of the QSH effect and the TSC.
Externe Organisation(en): Technische Universität Dresden
Julius-Maximilians-Universität Würzburg
Helmholtz-Zentrum Dresden-Rossendorf (HZDR)
Exzellenzcluster ct.qmat - Complexity and Topology in Quantum Matter
Technische Universität Braunschweig
Typ: Artikel
Journal: Physical Review B
Band: 101
ISSN: 2469-9950
Publikationsdatum: 15.06.2020
Publikationsstatus: Veröffentlicht
Peer-reviewed: Ja
ASJC Scopus Sachgebiete: Elektronische, optische und magnetische Materialien, Physik der kondensierten Materie
Elektronische Version(en): https://doi.org/10.1103/PhysRevB.101.235308 (Zugang: Unbekannt)

BibTeX

@article{f7b356162e93467883761d6c7562039b,
title = "Transport signatures of a junction between a quantum spin Hall system and a chiral topological superconductor",
abstract = "We investigate transport through a normal-superconductor (NS) junction made from a quantum spin Hall (QSH) system with helical edge states and a two-dimensional (2D) chiral topological superconductor (TSC) having a chiral Majorana edge mode. We employ a two-dimensional extended four-band model for HgTe-based quantum wells in a magnetic (Zeeman) field and subject to s-wave superconductivity. We show using the Bogoliubov-de Gennes scattering formalism that this structure provides a striking transport signal of a 2D TSC. As a function of the sample width (or Fermi energy) the conductance resonances go through a sequence of 2e2/h (nontrivial phase) and 4e2/h plateaux (trivial phase) which fall within the region of a nonzero Chern number (2D limit) as the sample width becomes large. These signatures are a manifestation of the topological nature of the QSH effect and the TSC.",
author = "Novik, {E. G.} and B. Trauzettel and P. Recher",
note = "Funding information: We thank R.W. Reinthaler for helpful discussions. We acknowledge financial support by DFG Grants No. AS 327/5-1 and No. RE 2978/7-1, the SFB 1143 (project-id 247310070), the SFB 1170 ToCoTronics, the W{\"u}rzburg-Dresden Cluster of Excellence ct.qmat (EXC 2147, project-id 39085490), and the DFG Excellence Strategy-EXC-2123 QuantumFrontiers-390837967.",
year = "2020",
month = jun,
day = "15",
doi = "10.1103/PhysRevB.101.235308",
language = "English",
volume = "101",
journal = "Physical Review B",
issn = "2469-9950",
publisher = "American Institute of Physics",
number = "23",
}