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  • Letter
  • Open Access

Phase-tunable electron transport assisted by odd-frequency Cooper pairs in topological Josephson junctions

Jorge Cayao1, Paramita Dutta2, Pablo Burset3, and Annica M. Black-Schaffer1

  • 1Department of Physics and Astronomy, Uppsala University, Box 516, S-751 20 Uppsala, Sweden
  • 2Theoretical Physics Division, Physical Research Laboratory, Navrangpura, Ahmedabad-380009, India
  • 3Department of Theoretical Condensed Matter Physics, Condensed Matter Physics Center (IFIMAC) and Instituto Nicolás Cabrera, Universidad Autónoma de Madrid, 28049 Madrid, Spain

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Phys. Rev. B 106, L100502 – Published 9 September, 2022

DOI: https://doi.org/10.1103/PhysRevB.106.L100502

Abstract

We consider a finite-size topological Josephson junction formed at the edge of a two-dimensional topological insulator in proximity to conventional superconductors and study the impact of Cooper pair symmetries on the electron transport. We find that, due to the finite junction size, electron transport is highly tunable by the superconducting phase difference ϕ across the junction. At zero frequency and ϕ=π, the setup exhibits vanishing local Andreev reflection and perfect normal transmission due to the interplay of finite junction size and formation of topological Andreev bound states in the middle of the junction. We reveal that this striking behavior enables odd-frequency Cooper pairs to become the only type of pairing inside the topological junction that contribute to transport. Our paper thus offers a highly tunable detection scheme for odd-frequency Cooper pairs.

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Phys. Rev. B 106, L100502– Published 9 September, 2022
  • Received 9 June 2022
  • Revised 15 August 2022
  • Accepted 26 August 2022
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