Roles of μSR: unveiling unconventional superconductivity of Sr2RuO4

by Prof. Yoshiteru Maeno (TRiKUC, Kyoto University, Japan)

Thursday 15 May 2025, 14:00 → 15:00 Europe/Zurich

SZ-WBGB/019

After thirty years of extensive investigations into the unconventional superconductivity in the layered perovskite Sr₂RuO₄, its pairing symmetry remains unresolved [1, 2]. Muon Spin Rotation (μSR) has played significant roles to disclose its novel superconducting phenomena. Broken time-reversal symmetry [3], splitting of the superconducting transition temperature Tc under uniaxial strain [4], surface magnetism attributable to chiral orbital current [5] are some of the examples of new physics emerging from Sr₂RuO₄. It is also used as a model system to clarify the effect of muons in the electronic structure by “DFT+μ” calculations [6].

In this talk, I will review the roles of μSR experiments in unveiling the unconventional superconductivity of Sr₂RuO₄. As the main topic, I will introduce our current efforts to extract the spin susceptibility of Sr₂RuO₄ from the measurements of the muon Knight shift using the FLAME spectrometer at PSI [7].

References
1. Y. Maeno, A. Ikeda, and G. Mattoni, Nat. Phys. 20, 1712 (2024).
2. Y. Maeno, A. Ramires, and S. Yonezawa, J. Phys. Soc. Jpn. 93, 062001 (2024).
3. G. Luke et al., Nature 394, 558‒561 (1998).
4. V. Grinenko et al., Nat. Phys. 17, 748 (2021).
5. R. Fittipaldi et al., Nat. Commun. 12, 5792 (2021).
6. S. Blundell and T. Lancaster, Appl. Phys. Rev. 10, 021316 (2023).
7. H. Matsuki, R. Khasanov, Y. Maeno et al., in preparation.