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Fabrication and Characterization of Superconducting Films for Superconductor-Topological Insulator Hybrid Devices

  • Xurui Zhang
  • Xiaoyan ShiEmail author
Original Paper
  • 1 Downloads

Abstract

Proximation of s-wave superconductivity to topological materials is an effective way to realize Majorana modes in condensed matter physics. In order to fabricate a successful device, the superconducting material plays a crucial role since selection of material, growth method, applicable critical temperature, adequate critical magnetic field, transparent electrical contact, and thus proper work function, needs to be deliberately considered. Here, we report the fabrications and transport measurements for two types of superconducting thin films, tantalum (Ta) and niobium nitride (NbN), at various growth conditions. Both Ta and NbN films show applicable potentials as the superconducting electrodes. We also demonstrate the proximity effect induced supercurrent state in an InAs/GaSb bilayer device with superconducting Ta electrodes.

Keywords

Superconductor Tantalum Niobium nitride Sputtering Thin film Upper critical magnetic field Magnetoresistance 

Notes

Funding information

This work was supported by UT Dallas research enhancement fund.

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of PhysicsThe University of Texas at DallasRichardsonUSA

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