Multiband mean-field theory of the $d+ig$ superconductivity scenario in Sr${}_2$RuO${}_4$

Abstract

Many seemingly contradictory experimental findings concerning the superconducting state in Sr${}_2$RuO${}_4$ can be accounted for on the basis of a conjectured accidental degeneracy between two patterns of pairing that are unrelated to each other under the $(D_{4h})$ symmetry of the crystal: a $d_{x^2-y^2}$-wave $(B_{1g})$ and a $g_{xy(x^2-y^2)}$-wave $(A_{2g})$ superconducting state. In this paper, we propose a generic multi-band model in which the $g$-wave pairing involving the $xz$ and $yz$ orbitals arises from second-nearest-neighbor interactions. Even if time-reversal symmetry is broken in a $d+ig$ state, such a superconductor remains gapless with a Bogoliubov Fermi surface that approximates a (vertical) line node. The model gives rise to a strain-dependent splitting between the critical temperature $T_c$ and the time-reversal symmetry-breaking temperature $T_{\text{trsb}}$ that is qualitatively similar to some of the experimental observations in Sr${}_2$RuO${}_4$.

21 pages (including Appendix), 4 figures

References in corpus (19)

• High Resolution Polar Kerr Effect Measurements of Sr2RuO4: Evidence for Broken Time Reversal Symmetry in the Superconducting State
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• Shadowed triplet pairings in Hund's metals with spin-orbit coupling
• Spin Density Wave Fluctuations and p-wave Pairing in Sr2RuO4
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• Leading superconducting instabilities in three-dimensional models for Sr2RuO4
• Strain-induced time reversal breaking and half quantum vortices near a putative superconducting tetra-critical point in Sr${}_2$RuO${}_4$
• Higher angular momentum pairing states in Sr${}_2$RuO${}_4$ in the presence of longer-range interactions
• Multipole-fluctuation pairing mechanism of $d_{x^2-y^2}+ig$ superconductivity in Sr${}_2$RuO${}_4$

Cited by in corpus (8)

• Altermagnetism and superconductivity in a multiorbital t-J model
• Constraints on the superconducting state of Sr${}_2$RuO${}_4$ from elastocaloric measurements
• Competition between d-wave superconductivity and magnetism in uniaxially strained Sr2RuO4
• Conditions for orbital selective altermagnetism in Sr${}_2$RuO${}_4$: tight binding model, similarities with cuprates and implications on superconductivity
• Pairing susceptibility in the weakly interacting multilayer Hubbard model evaluated by direct perturbative expansion
• Phase sensitive information from a planar Josephson junction
• Influence of Fermi Surface Geometry and Van Hove Singularities on the Optical Response of Sr${}_2$RuO${}_4$
• Evolution and Instability of Bogoliubov Fermi Surfaces under Zeeman Field