Induced unconventional superconductivity on the surface states of Bi2Te3 topological insulator
Journal article, 2017

Topological superconductivity is central to a variety of novel phenomena involving the interplay between topologically ordered phases and broken-symmetry states. The key ingredient is an unconventional order parameter, with an orbital component containing a chiral p(x) + ip(y) wave term. Here we present phase-sensitive measurements, based on the quantum interference in nanoscale Josephson junctions, realized by using Bi2Te3 topological insulator. We demonstrate that the induced superconductivity is unconventional and consistent with a sign-changing order parameter, such as a chiral px + ipy component. The magnetic field pattern of the junctions shows a dip at zero externally applied magnetic field, which is an incontrovertible signature of the simultaneous existence of 0 and pi coupling within the junction, inherent to a non trivial order parameter phase. The nano-textured morphology of the Bi2Te3 flakes, and the dramatic role played by thermal strain are the surprising key factors for the display of an unconventional induced order parameter.

bi2se3

junctions

edge

symmetry

strain

thin-films

Author

Sophie Charpentier

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

luca galletti

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Gunta Kunakova

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Riccardo Arpaia

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Yuxin Song

Chalmers, Microtechnology and Nanoscience (MC2), Photonics

Reza Baghdadi

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Shu Min Wang

Chalmers, Microtechnology and Nanoscience (MC2), Photonics

Alexei Kalaboukhov

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Eva Olsson

Chalmers, Physics, Eva Olsson Group

Francesco Tafuri

Universita degli Studi di Napoli Federico II

Superconductors, oxides and other innovative materials and devices

Dmitry Golubev

Aalto University

Jacob Linder

Norges teknisk-naturvitenskapelige universitet

Thilo Bauch

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Floriana Lombardi

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Nature Communications

2041-1723 (ISSN)

Vol. 8 1 2019

Subject Categories

Physical Sciences

DOI

10.1038/s41467-017-02069-z

PubMed

29222507