Olivier GINGRAS : Superconducting Strontium Ruthenate: The Enigma Persists Despite Recent Advancements

Olivier GINGRAS (Center for Computational Quantum Physics, Flatiron Institute, New York)

The resume:

Over the past three decades, the superconducting state of strontium ruthenate has fueled intensive research. Despite substantial progress, a consensus on the symmetry of its order parameter remains elusive. Although the d-wave state has gained favor in recent years, perplexing experimental observations, including time-reversal symmetry breaking and multi-component signatures, challenge its completeness.

We undertake a comprehensive overview of the current understanding of this material, then explore three distinct computational approaches used to investigate its superconducting state. The first employs the Eliashberg equation to inspect the pairing susceptibility from the normal state. The second leverages the functional renormalization group to investigate the phase diagram. The third explores the linear response to dynamical external pairing fields. Overall, the results of these approaches reinforce the prevalence of the d-wave state, while also hinting at odd-frequency pairing as a potential second component.

Contact: andrej.mesaros@universite-paris-saclay.fr