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  • Letter
  • Open Access

Proposal for identifying possible even-parity superconducting states in Sr2RuO4 using planar tunneling spectroscopy

Satoshi Ikegaya1,2, Shu-Ichiro Suzuki2, Yukio Tanaka2, and Dirk Manske1

  • 1Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
  • 2Department of Applied Physics, Nagoya University, Nagoya 464-8603, Japan

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Phys. Rev. Research 3, L032062 – Published 13 September, 2021

DOI: https://doi.org/10.1103/PhysRevResearch.3.L032062

Abstract

After more than 25 years of research, three even-parity superconducting states—the d+id-wave, d+ig-wave, and s+id-wave states—have emerged as leading candidates for the superconducting states of Sr2RuO4. In the present work, we propose a tunneling spectroscopy experiment for distinguishing among these three superconducting states. The key component of our proposal is that we examine the conductance spectra of normal-metal/Sr2RuO4 junctions with various angles between the junction interface and the crystal axis of the Sr2RuO4. The angle dependence of the conductance spectra shows a unique pattern in each superconducting state, which can function as a fingerprint for verifying the pairing symmetry of Sr2RuO4.

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Phys. Rev. Research 3, L032062– Published 13 September, 2021
  • Received 17 June 2021
  • Revised 15 July 2021
  • Accepted 10 August 2021
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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. Open access publication funded by the Max Planck Society.

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