Absence of a Proximity Effect in a Topological Insulator on a Cuprate Superconductor: Bi2Se3/Bi2Sr2CaCu2O8

Abstract

Proximity-induced superconductivity in a 3D topological insulator represents a new avenue for observing zero-energy Majorana fermions inside vortex cores. Relatively small gaps and low transition temperatures of conventional s-wave superconductors put the hard constraints on these experiments. Significantly larger gaps and higher transition temperatures in cuprate superconductors might be an attractive alternative to considerably relax these constraints, but it is not clear whether the proximity effect would be effective in heterostructures involving cuprates and topological insulators. Here, we present angle-resolved photoemission studies of thin Bi2Se3 films grown in-situ on optimally doped Bi2Sr2CaCu2O8 substrates that show the absence of proximity-induced gaps on the surfaces of Bi2Se3 films as thin as a 1.5 quintuple layer. These results suggest that the superconducting proximity effect between a cuprate superconductor and a topological insulator is strongly suppressed, likely due to a very short coherence length along the c-axis, incompatible crystal and pairing symmetries at the interface, small size of the topological surface state Fermi surface and adverse effects of a strong spin-orbit coupling in the topological material.

Work presented at the March Meeting of American Physical Society in Denver on March 3, 2014

References in corpus (6)

• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Pressure induced Superconductivity in Topological Compound Bi2Te3
• Bulk superconducting phase with a full energy gap in the doped topological insulator Cu_xBi_2Se_3
• The Ground State of the Pseudogap in Cuprate Superconductors
• Proximity-induced high-temperature superconductivity in topological insulators Bi2Se3 and Bi2Te3
• Coexistence of metallicity and superconductivity in adjacent bilayers of a high-Tc superconductor

Cited by in corpus (5)

• Momentum space imaging of Cooper pairing in a half-Dirac-gas topological superconductor (a helical 2D topological superconductor)
• On the interplay of paramagnetism and topology in the Fe-based High Tc Superconductors
• Observation of the anisotropic Dirac cone in the band dispersion of 112-structured iron-based superconductor Ca0.9La0.1FeAs2
• Modeling Tunneling for the Unconventional Superconducting Proximity Effect
• Andreev Reflection without Fermi surface alignment in High T${}_c$-Topological heterostructures