Influence of uniaxial pressure and spin-orbit coupling on spin fluctuations in superconducting strontium ruthenate*

Strontium ruthenate has one of the best characterized normal-state Fermi-liquid. Since experiments and theory give contradictory results, predicting its superconducting order parameter from first principles has thus become an important challenge. Studies of superconductivity based on a correlated electronic structure and spin-fluctuation theory have predicted three possible order parameters but neglected spin-orbit coupling [1], although it was shown that this coupling might be important [2]. We evaluate ab initio the effect of spin-orbit coupling on the spin fluctuations that act as pairing glue and discuss its impact on superconductivity. Moreover, we investigate the effect of uniaxial pressure on these fluctuations because experiments have revealed intriguing behaviors under such conditions [3].

[1] Gingras et al., Phys. Rev. Lett. 123, 217005 (2019)
[2] Tamai et al., Phys. Rev. X 9, 021048 (2019)
[3] Steppke et al., Science 355, 148 (2017)