p-wave triggered superconductivity in single layer graphene on an electron-doped oxide superconductor

Angelo Di Bernardo; Oded Millo; Matteo Barbone; Hen Alpern; Yoav Kalcheim; Ugo Sassi; Anna Ott; Domenico De Fazio; Duhee Yoon; Mario Amado; Andrea C. Ferrari; Jacob Linder; Jason W. A. Robinson

doi:10.1038/ncomms14024

arXiv · 1702.01572

p-wave triggered superconductivity in single layer graphene on an electron-doped oxide superconductor

Angelo Di Bernardo·Oded Millo·Matteo Barbone·Hen Alpern·Yoav Kalcheim·Ugo Sassi·Anna Ott·Domenico De Fazio·Duhee Yoon·Mario Amado·Andrea C. Ferrari·Jacob Linder·Jason W. A. Robinson

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Abstract

Electron pairing in the vast majority of superconductors follows the Bardeen-Cooper-Schrieffer theory of superconductivity, which describes the condensation of electrons into pairs with antiparallel spins in a singlet state with an s-wave symmetry. Unconventional superconductivity is predicted in single layer graphene where the electrons pair with a p-wave or chiral d-wave symmetry, depending on the position of the Fermi energy with respect to the Dirac point. By placing single layer graphene on an electron-doped (non-chiral) d-wave superconductor and performing local scanning tunnelling microscopy and spectroscopy, here we show evidence for a p-wave triggered superconducting density of states in single layer graphene. The realization of unconventional superconductivity in single layer graphene offers an exciting new route for the development of p-wave superconductivity using two-dimensional materials with transition temperatures above 4.2 K.

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Angelo Di Bernardo, Oded Millo, Matteo Barbone, Hen Alpern, Yoav Kalcheim, Ugo Sassi, Anna Ott, Domenico De Fazio, Duhee Yoon, Mario Amado, Andrea C. Ferrari, Jacob Linder, Jason W. A. Robinson. 2017-02-06. p-wave triggered superconductivity in single layer graphene on an electron-doped oxide superconductor. https://doi.org/10.1038/ncomms14024

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