Josephson Effect and Charge Distribution in Thin Bi2 Te3 Topological Insulators

Martin P Stehno; Prosper Ngabonziza; Hiroaki Myoren; Alexander Brinkman

doi:10.1002/adma.201908351

Josephson Effect and Charge Distribution in Thin Bi₂ Te₃ Topological Insulators

Adv Mater. 2020 Apr;32(14):e1908351. doi: 10.1002/adma.201908351. Epub 2020 Feb 24.

Authors

Martin P Stehno^{1

2}, Prosper Ngabonziza^{1

3

4}, Hiroaki Myoren⁵, Alexander Brinkman¹

Affiliations

¹ Faculty of Science and Technology and MESA+ Institute for Nanotechnology, University of Twente, 7500 AE, Enschede, The Netherlands.
² Physikalisches Institut EP3, University of Würzburg, Am Hubland, 97070, Würzburg, Germany.
³ Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany.
⁴ Department of Physics, University of Johannesburg, P.O. Box 524 Auckland Park, 2006, Johannesburg, South Africa.
⁵ Graduate school of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570, Japan.

PMID: 32091158
DOI: 10.1002/adma.201908351

Abstract

Thin layers of topological insulator materials are quasi-2D systems featuring a complex interplay between quantum confinement and topological band structure. To understand the role of the spatial distribution of carriers in electrical transport, the Josephson effect, magnetotransport, and weak anti-localization are studied in bottom-gated thin Bi₂ Te₃ topological insulator films. The experimental carrier densities are compared to a model based on the solutions of the self-consistent Schrödinger-Poisson equations and they are in excellent agreement. The modeling allows for a quantitative interpretation of the weak antilocalization correction to the conduction and of the critical current of Josephson junctions with weak links made from such films without any ad hoc assumptions.

Keywords: Josephson junctions; bismuth telluride; diffusive transport; superconductivity; topological insulators.

Abstract

Grants and funding