Proximity Effect in a Topological Insulator on a Cuprate d-wave Superconductor

ORAL

Abstract

Proximity induced $s$-wave superconductivity in a 3D topological insulator (TI) represents a new avenue for observing zero-energy Majorana fermions inside the vortex cores. A relatively small gap and a low transition temperature of conventional $s$-wave superconductors put the hard constraints on these experiments. Larger gaps and higher transition temperatures in cuprate superconductors would significantly relax these constraints, but with intrinsic zero-energy modes in vortex cores, it is not clear if Majorana fermions could be resolved. Here, we present our angle-resolved photoemission studies of thin TI films grown $in$-$situ$ on optimally doped Bi2212 substrates. We discuss the obtained thickness dependence and the symmetry of the gap induced in the topological surface state on the prospects of detecting Majorana modes in such systems.

Authors

  • Tonica Valla

    Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Brookhaven National Laboratory, Brookhaven Natl Lab

  • Turgut Yilmaz

    University of Connecticut

  • Ivo Pletikosic

    Department of Chemistry, Princeton University, Princeton University, Princeton University \& Brookhaven Natl Lab

  • Andrew Weber

    Department of Physics and Astronomy, University of Missouri-Kansas City, Brookhaven Natl Lab

  • Genda Gu

    Brookhaven National Laboratory, Condensed Matter Physics and Materials Science Department, Brookhaven National laboratory, Brookhaven Natl Lab, Brookhaven National Lab, Brookhaven National Labs

  • Elio Vescovo

    National Synchrotron Light Source, Brookhaven National Laboratory, Brookhaven Natl Lab

  • Boris Sinkovic

    University of Connecticut