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  • Letter
  • Open Access

Signature of long-ranged spin triplets across a two-dimensional superconductor/helimagnet van der Waals interface

A. Spuri1, D. Nikolić1,2, S. Chakraborty1, M. Klang3, H. Alpern3, O. Millo3, H. Steinberg3, W. Belzig1, E. Scheer1 et al.

A. Di Bernardo1,4,*

  • 1Department of Physics, University of Konstanz, 78457 Konstanz, Germany
  • 2Institut für Physik, Universität Greifswald, Felix-Hausdorff-Strasse 6, 17849 Greifswald, Germany
  • 3Racah Institute of Physics, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel
  • 4Dipartimento di Fisica “E. R. Caianiello,” Università degli Studi di Salerno, I-84084 Fisciano (SA), Italy

  • *Corresponding author: angelo.dibernardo@uni-konstanz.de
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Phys. Rev. Research 6, L012046 – Published 1 March, 2024

DOI: https://doi.org/10.1103/PhysRevResearch.6.L012046

Abstract

The combination of a superconductor with a magnetically inhomogeneous material has been established as an efficient mechanism for the generation of long-ranged spin-polarized (spin-triplet) Cooper pairs. Evidence for this mechanism, however, has been demonstrated based on studies done on thin-film multilayers, where the strong bonds existing at the interface between the superconductor and the magnetic material should in principle enhance proximity effects and strengthen any electronic correlations. Here, we fabricate devices based on van der Waals (vdW) stacks of flakes of the NbS2 combined with flakes of Cr1/3NbS2, which has a built-in magnetic inhomogeneity due to its helimagnetic spin texture at low temperatures. We find that the critical temperature of these vdW heterostructures is strongly dependent on the magnetic state of Cr1/3NbS2, whose degree of magnetic inhomogeneity can be controlled via an applied magnetic field. Our results demonstrate evidence for the generation of long-ranged spin-triplet pairs across the Cr1/3NbS2/NbS2 vdW interface.

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Phys. Rev. Research 6, L012046– Published 1 March, 2024
  • Received 6 May 2023
  • Revised 8 August 2023
  • Accepted 11 January 2024
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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