Sr<sub>2</sub>RuO<sub>4</sub> Josephson junctions built in epitaxial films

ORAL

Abstract

A layered-perovskite superconductor Sr2RuO4 has attracted continuing interest as a leading candidate with chiral p-wave symmetry, which is one of topological superconductors potentially hosting Majorana fermions. For further investigation and possible applications of the unique state, the use of Sr2RuO4 thin films for junctions has been increasingly demanded. While growth of the superconducting Sr2RuO4 films had been extremely difficult over the past decades [1,2], the reproducible and controllable growth has been recently achieved by refining molecular beam epitaxy techniques [3]. In this talk, we report fundamental superconducting properties of Sr2RuO4 thin films and also Josephson junctions as revealed by systematic ultralow-temperature transport measurement. The Sr2RuO4-Sr2RuO4 Josephson junctions built in the epitaxial films have some advantages in investigating the possible multicomponent order parameter. The observed IcRn product is as high as 2 μeV and its temperature dependence shows clear deviations from the conventional Ambegaokar-Baratov model.

[1] Y. Krockenberger et al., Appl. Phys. Lett. 97, 082502 (2010).
[2] J. Cao et al., Supercond. Sci. Technol. 29, 095005 (2016).
[3] M. Uchida et al., APL Mater. 5, 106108 (2017).

–

Presenters

  • Masaki Uchida

    • University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), the University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), Univ. of Tokyo, Tokyo, Japan.

Authors

  • Masaki Uchida

    • University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), the University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), Univ. of Tokyo, Tokyo, Japan.

  • Ikkei Sakuraba

    • University of Tokyo

  • Minoru Kawamura

    • RIKEN CEMS
    • CEMS, RIKEN

  • Motoharu Ide

    • University of Tokyo

  • Kei Takahashi

    • RIKEN CEMS
    • CEMS, RIKEN
    • Center for Emergent Matter Science, RIKEN

  • Yoshinori Tokura

    • RIKEN Center for Emergent Matter Science (CEMS)
    • RIKEN Center for Emergent Matter Science
    • RIKEN CEMS
    • RIKEN Center for Emergent Matter Science (CEMS), Wako, Japan
    • Center for Emergent Matter Science (CEMS), RIKEN
    • Department of Applied Physics and Quantum-Phase Electronics Center, University of Tokyo
    • University of Tokyo
    • University of Tokyo and RIKEN CEMS
    • CEMS, RIKEN
    • Center for Emergent Matter Science, RIKEN
    • Department of Applied Physics, University of Tokyo
    • University of Tokyo and RIKEN-CEMS

  • Masashi Kawasaki

    • The University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), The University of Tokyo, Tokyo 113-8656, Japan
    • University of Tokyo
    • Applied Physics and QPEC, University of Tokyo
    • Department of applied physics, The University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), the University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), Univ. of Tokyo, Tokyo, Japan.