Topological superconductivity in a phase-controlled Josephson junction

Hechen Ren, Falko Pientka, Sean Hart, Andrew T. Pierce, Michael Kosowsky, Lukas Lunczer, Raimund Schlereth, Benedikt Scharf, Ewelina M. Hankiewicz, Laurens W. Molenkamp, Bertrand I. Halperin and Amir Yacoby ()
Additional contact information
Hechen Ren: Harvard University
Falko Pientka: Harvard University
Sean Hart: Harvard University
Andrew T. Pierce: Harvard University
Michael Kosowsky: Harvard University
Lukas Lunczer: Universität Würzburg
Raimund Schlereth: Universität Würzburg
Benedikt Scharf: Universität Würzburg
Ewelina M. Hankiewicz: Universität Würzburg
Laurens W. Molenkamp: IBM T. J. Watson Research Center
Bertrand I. Halperin: Harvard University
Amir Yacoby: Harvard University

Nature, 2019, vol. 569, issue 7754, 93-98

Abstract: Abstract Topological superconductors can support localized Majorana states at their boundaries1–5. These quasi-particle excitations obey non-Abelian statistics that can be used to encode and manipulate quantum information in a topologically protected manner6,7. Although signatures of Majorana bound states have been observed in one-dimensional systems, there is an ongoing effort to find alternative platforms that do not require fine-tuning of parameters and can be easily scaled to large numbers of states8–21. Here we present an experimental approach towards a two-dimensional architecture of Majorana bound states. Using a Josephson junction made of a HgTe quantum well coupled to thin-film aluminium, we are able to tune the transition between a trivial and a topological superconducting state by controlling the phase difference across the junction and applying an in-plane magnetic field22. We determine the topological state of the resulting superconductor by measuring the tunnelling conductance at the edge of the junction. At low magnetic fields, we observe a minimum in the tunnelling spectra near zero bias, consistent with a trivial superconductor. However, as the magnetic field increases, the tunnelling conductance develops a zero-bias peak, which persists over a range of phase differences that expands systematically with increasing magnetic field. Our observations are consistent with theoretical predictions for this system and with full quantum mechanical numerical simulations performed on model systems with similar dimensions and parameters. Our work establishes this system as a promising platform for realizing topological superconductivity and for creating and manipulating Majorana modes and probing topological superconducting phases in two-dimensional systems.

Date: 2019
References: Add references at CitEc
Citations: View citations in EconPapers (3)

Downloads: (external link)
https://www.nature.com/articles/s41586-019-1148-9 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:569:y:2019:i:7754:d:10.1038_s41586-019-1148-9

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/s41586-019-1148-9

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().